What is it?

Fantasia Apocalyptica is a multimedia work for pipe organ, accompanied by several video tracks. It can be regarded as a somewhat literal translation of the Biblical book of Revelation into music.

Why did you write it?

‘Revelation’, also known as ‘Apocalypse’ (‘Uncovering’), is a mystical book that's filled with symbols. It consists chiefly of a dream, recorded in the first century A.D. by Saint John the Divine. The dramatic events in his famous dream run the gamut of human emotions, as they highlight crucial aspects of life, death, and spirituality.

I was introduced to Revelation by a faculty colleague at Caltech in the early 60s, and was especially fascinated by the ways in which many different numbers (2, 3, 3.5, 4, 7, 12, 24, …) were emphasized and given symbolic significance. At about the same time, as a member of the choir at my church, I happened to learn Paul Manz's wonderful anthem ‘E'en so, Lord Jesus, Quickly Come’, which is based on the book of Revelation.

An intriguing notion was soon planted in my head, namely that it might be possible to create a pleasing piece of music that incorporates Revelation's numbers and other mystical symbols in essentially their original order. (Paul Manz happens to be one of my shirt-tail relatives. I asked him early on if he would allow me to quote from his anthem, if I should ever write such a piece, and he happily encouraged me to pursue the idea.)

In 1969 I audited a music theory class at Westminster Choir College in Princeton. One of the assignments was to set a short text to music, and I chose to experiment with the phrase “I am Alpha and Omega” found in Revelation 1:8 and 21:6. The teacher told me that his favorite setting of those words was by Sir John Stainer, and he gleefully sang Stainer's melody. Thus I began to learn of the vast number of musical compositions that have been inspired by John the Divine's dream, and my vague plan of going further was reinforced.

“I want to write some music for organ with computer help. If I live long enough, I would like to write a rather long work that would be based on the book of Revelation. The musical themes would correspond to the symbolism in the book.” -- from an interview by Donald Albers and Lynn Steen, 12 January 1981

Many years went by, as my time was consumed by other projects. Yet the notion of Revelation-in-music stayed with me, and I finally began to realize that I had better get started, if I'm ever going to finish. Therefore I started to make plans in earnest. On the day before Thanksgiving in 2011 — when I was nearly 74 years old, and after I'd spent much of the day working as usual on The Art of Computer Programming — I took a blank notebook out of storage and wrote the following:

In this book I plan to jot down thoughts for a project that may be crazy, but a “muse” has been encouraging me to embark upon it for more than 40 years. … I should mention that I consider [the book of Revelation] to be totally mystical and spiritual rather than literal or prophetical. It probably was written to provide an underground movement (early Christianity) with some coded messages of hope. But I'm intrigued by the fact that so many artists and writers have been inspired by these words, for nearly 2000 years by now; thus I can't resist the thought that perhaps I too might be led by this ancient text to create something that may be newly meaningful to people of the 21st century. Of course I may fail totally, and any music I write might be basically worthless. But, as I said, something has been urging me to do this for a long time, and I find that I cannot resist trying.

I learned a bit later that Victorinus of Poetovio, who wrote the first full-length commentary on Revelation (c. 270 A.D.), had already remarked with admiration that Revelation is organized rather like a piece of music, in that its repetitions of symbols and themes don't simply unfold in straight lines.

In what style did you write it?

Fantasia Apocalyptica doesn't conform to any fixed style. It's basically a 21st-century mashup of many styles that have appeared in previous centuries. Indeed, the book of Revelation ranges over many different moods; hence a single style can't do justice to them all. Elements of at least the following styles can be found within this piece, in addition to styles that are specific to pipe organ classics:

  1. ancient Greek music
  2. medieval chants
  3. changeringing
  4. Baroque counterpoint
  5. near-Eastern folk music
  6. shape note singing
  7. Romantic chorales and oratorios
  8. Romantic combinatorial patterns
  9. atonal “12-tone” music
  10. close harmony and jazz
  11. Broadway musical comedy
  12. rock music and rap music

And of course a musical work on the Apocalypse should also contain calypso.

I consciously tried to avoid constructing a mere ‘pastiche’, and emphatically not a ‘hodge-podge’! The result that I came up with does have its own characteristic flavor, rather different from most other music that I've ever heard. I think of it as having “high bandwidth”, in the sense that the musical ideas change somewhat rapidly (although they do recur in patterns). I don't pause to wait until the listener “gets it”; instead, I hope that the listener will appreciate a bit more every time the piece is heard.

I was delighted to find that a pipe organ is ideally suited to the varied elements of this composition. Conversely, the themes of Revelation provide an ideal vehicle for demonstrating an organ's unique qualities. I fantasize that people who are unfamiliar with organ music will be able to understand why I love the instrument so much, after hearing this piece.

Have you written much music before?

I spent a lot of time in high school reading books on orchestration, and I wrote a fairly good-sized work for symphonic band entitled Milton and the Rhinoceros. (It was a spoof of Peter and the Wolf, using a story by Roger Price that I didn't know was protected by copyright. I was blithely ignorant about intellectual property.) I proudly presented that piece to the band director, and he proceeded to lose it. As far as I know, no trace of that piece remains; and everybody, including me, is probably better off as a result.

I also wrote some short works in high school and in college, then a few occasionally as an adult. The best of these have been collected in Chapters 19–21 of my Selected Papers on Fun & Games. There also are some hymn arrangements, on pages 646–647 of that book and on page 88 of Things a Computer Scientist Rarely Talks About.

In short, Fantasia Apocalyptica is far more extensive than anything else that I've ever attempted to write. I have, however, spent thousands of hours playing the works of other composers, hopefully learning a thing or two in the process.

Is Fantasia Apocalyptica ‘computer music’ — generated by algorithms?

At one point I thought I might have time to understand music theory well enough that I could try to teach that theory to a computer. But eventually I concluded that it would be better to create this piece almost entirely by hand, using my desktop machine only to help organize the work. Thus it's definitely not “computer music”, although I do profess to be a computer scientist.

On the other hand, I did apply some algorithms manually in a few places. For example, a haunting melody, taken from one of the earliest surviving instances of ancient Greek music, occurs ten times. I harmonized it differently each time, using the algorithm of David Kraehenbuehl that's described in Chapter 22 of Selected Papers on Fun & Games. (See “Randomness in Music”.)

Mathematical methods were also used to generate the changeringing patterns that appear briefly, as well as certain melodies used for the twelve tribes of Israel and for the twelve precious jewels below the “pearly gates” of the New Jerusalem. If those methods hadn't been successful, I would have changed the results by hand. Fortunately, I didn't have to do that; the algorithmic approach did give a pleasing result in those cases.

What compositional methods did you use?

First I prepared myself by reading several books about composition, by Stainer, Schoenberg, Hindemith, Piston, and others.

Then, instead of relying on algorithms, I did constraint-based composition, which is a methodology that I discussed in an hour-long lecture to Stanford's musicians on 07 May 2015. The basic idea was to study the Greek text carefully and to identify roughly 150 of the principal motifs that it contains. For every such textual motif, I then chose a corresponding musical motif to use as its translation. (Think of Wagner's “leitmotifs”.)

Some of these musical motifs are brief melodies; some are chords; some are rhythms; some are idioms like trills, arpeggios, appoggiaturas, contrary motion; some are effects possible only on a pipe organ; and so on. Eight of them are up-down patterns inspired by the I Ching. Several of them are much less specific: I simply told myself to think of a certain composer. (For ‘truth’ I thought of Bach; for ‘voice’ I thought of Borodin; etc.) People who are obsessively curious can find below the complete dictionary of motifs that I finally selected.

Then, for each of the 404 verses in the book of Revelation, I made a list of the textual motifs that they contain, and the order in which those motifs occur.

I also searched systematically for existing musical works that were inspired by passages in the book of Revelation. Franz Schmidt wrote the longest of these, Das Buch mit sieben Siegeln (1938), a major oratorio composed for choir, organ, and a rather large symphony orchestra. (Its reduced piano score has more than 200 pages; yet it covers less than half of Revelation's text.) Other major works include Johannes Brahms's Triumphlied (1872), Charles Gounod's Mors et Vita (1884), etc., and a great many shorter anthems. Altogether I collected about 70 such works, and crosslinked them into my verse-by-verse database. I was mindful of Johann Mattheson's advice from 1739:

A composer might make a collection of all the pleasing motives that he has encountered. … Even the greatest capitalists will borrow money if it is to their advantage or convenience. … But copied work should be returned with interest.

So now I was ready to compose music for any particular verse, based on a reasonably short list of constraints. Every constraint narrowed down the number of possibilities. My job, therefore, when translating a particular line of Revelation, was to come up with music that had a certain melody and/or rhythm and/or musical effect, etc. Of course I also had to keep the global context in mind, as well as those local constraints. The overriding goal was to create good music, without sacrificing too many of the constraints. (My principal model for this activity was the constraint-based literature produced by the Oulipo group, and especially by its brilliant contributor Georges Perec.)

I woke up one day with the music for the first few bars in my head. And I knew that I wanted to quote from Paul Manz near the end. But otherwise I worked inside out — here's an excerpt from my notebook entry for 21 March 2013:

At this point I've gathered more than enough music, and surveyed all of about 250 motifs that are potentially significant. So I guess the next step should be to plunge in, somewhere in the middle where my lack of experience won't stand out when all is complete. While biking home today I decided to start in verse 16:3, not knowing what it would be. So I just now looked at it: It's the second bowl of wrath, where sea turns to blood; and I guess it does make a decent test case for getting into the thick of things. (I found no previous music for chapters 16 or 17, so this doesn't impinge on many other decisions.) Verse 16:3 will need musical motifs for angel, bowl, sea, blood, and death.

During March 2013 I was mainly working on a difficult program for Section 7.2.2.2 of The Art of Computer Programming. But on 23 March I was able to write

OK! I'm working on SAT13, but in odd moments the music for 16:3 “came to me” and I like it! First, an excellent angel motif is an 8-note upward arpeggio (as at beginning of Waltz of Flowers, which goes 16 up then 16 down, so I can dwell on it differently for different angels in different contexts). Second, a bowl is represented by two notes on one manual that “confine” the notes in another manual between them; these boundary notes get closer and closer as the bowl tips, and the contents then spill out. Third, wrath in the bowl is indicated by a lively jumping/gurgling theme (although confined to only two notes when it's inside the bowl). Fourth, blood coagulates/curdles and gets heavy, hence I can use notes that are clotted in clusters. Fifth, there's room for just about any four-note motif in the pedal, in the last bars of this verse, so I can put in whatever pattern I eventually decide on for the sea and/or death. …

In May of 2013 I happened to be in Vienna. So I asked my hosts where Beethoven, Schubert, and Brahms had purchased the blank staff paper on which they wrote their music. I was referred to Musikhaus Doblinger, where I purchased a beautiful, handbound Notenschreibbuch in quarto format. And indeed, I believe that the opportunity to write out my fantasy in such a book has been advantageous. (Of course I wrote in pencil, and made frequent erasures. Real musicians use pen and ink.)

Little by little I was able to assign musical motifs to textual motifs, always trying to keep maximum flexibility for any decisions that could be postponed. After drafting part of chapter 16, I planned some of the key excerpts that appear in other chapters. Then I finally was ready to work more systematically and to complete entire chapters, working sporadically over a period of many months. I drafted roughly every third chapter before working on the chapters between them, so that I could keep the overall structure more clearly in mind.

The last thing I wrote was chapter 1. (That's typical. Years ago I'd written Chapter 1 of The Art of Computer Programming only after having completed a 3000-page pencil draft of all the other planned chapters.) Chapter 1 of Fantasia Apocalyptica was finished, hooray, on 20 August 2016.

During this process I often felt as if I were “channelling” — as if the music had already been written. Somehow the notes were already out there; I simply had to listen for them and to write them down.

Sometimes the music did indeed essentially write itself. But at other times I had to listen very hard before I could hear it. I often worked backward from a musical destination that I wanted to reach, as well as forward from previously written sections. Of course I'd often have to go back and start over, when the results didn't jell.

The whole process was quite exhilarating as well as exhausting. Unfortunately, it turned out to be very hard on my wife, because she had to hear all the false starts. Hence I did most of the work when she was out of the house.

Here's a fairly comprehensive lecture that describes all of the above, filmed at the University of Waterloo in November, 2018, including dozens of detailed examples. You can also watch an informal discussion about the general principles of constraints as a source of inspiration, filmed the next day.

How long is this piece?

According to the metronome markings in the score, a mechanical performance should take roughly 70 minutes. But when played with appropriate emotions, the total time turns out to be about 90 minutes. (For comparison, the time to play all 18 movements of Messiaen's Livre de Saint Sacrement is 114 minutes.)

The piece is, however, divided into 22 chapters, corresponding to the 22 chapters in the book of Revelation. Many of these chapters stand alone, and they can meaningfully be performed as organ voluntaries, lasting four or five minutes each. Indeed, it is best to think of this work as 22 individual pieces that share common themes.

When the entire work is performed, the accompanying video tracks will make it easy for listeners to know what part of the story is currently being played.

What are the video tracks mentioned above?

Track #1 shows Duane Bibby's superb illustrations of the Revelation story, especially commissioned for this work;
Track #2 shows the original Greek text of Revelation [the authorized 1904 text of the Ecumenical Patriarchate of Constantinople] as well as an English translation [Today's English Version];
Track #3 shows the organ score, more-or-less as seen by the performer;
Track #4 shows Stephen Malinowski's animation of the music, created with his brilliant Music Animation Machine.

[Track #4 is planned but not yet complete.]

The complete artwork of track #1 has been published in the book Fantasia Apocalyptica Illustrated, together with corresponding excerpts from tracks #2 and #3,

Is the work copyrighted?

I've chosen to use the Creative Commons ‘CC0’ tool (“no rights reserved”), thereby essentially putting the music of this work into the public domain. This means that you can copy it and modify it and remix it, etc., without feelings of guilt. If you want to acknowledge my role in its creation, that's great; but I created it only because I figured that somebody ought to do so. Links for downloading the music can be found below.

On the other hand, some of the information on the video tracks will be copyrighted separately. For example, the English translation in Track #2, “Today's English Version”, is copyright by the American Bible Society. And Duane Bibby's images in Track #1 have been published as a separate book.

Has the entire work been performed?

One of the greatest highlights of my life was to celebrate the world première of Fantasia Apocalyptica on my 80th birthday — Wednesday, 10 January 2018. This happy event took place on the magnificent new Woehl organ, in the magnificent performance space at Studio Acusticum in Piteå, Sweden. An outstanding Canadian organist, Jan Overduin, devoted much of his time during 2017 to mastering all of the nuances of this devilishly difficult piece, and he wedded the music brilliantly to Organ Acusticum — an ideal instrument for every aspect of this composition. (see the program)

Furthermore, a team from Google Research used state-of-the-art video and audio recording equipment to capture Jan's première performance, so that future viewing in “virtual reality” will be possible.

North American premières are also being planned, of course. For example, Overduin performed the complete work on the 44-stop Kney tracker organ at First United Church in Waterloo, Ontario, on Sunday, 4 November 2018. [Thank goodness he had miraculously recovered from a serious stroke, suffered at the beginning of March 2018.]

The third performance of the complete work took place on Friday, October 11, 2019, at the Jesuit Church of the Assumption of the Virgin Mary in Brno. Organist Jan Rotrekl played it superbly on their new Hermann Mathis pipe organ.

The Califonia première took place on the famous Ruffati organ at the Cathedral of St. Mary of the Assumption in San Francisco, as part of their weekly series of Musical Meditations. These concerts are 45 minutes long, and the Fantasia is 90 minutes long; therefore Part 1 was performed on Sunday December 5 at 4pm, and Part 2 was performed on Sunday December 12 at 4pm. Jin Kyung Lim, who helped me significantly as I was composing this work, was the organ soloist.

We had planned to have the California première in 2020, as part of the 100th Anniversary Celebration at First Lutheran Church in Palo Alto. But alas, the widespread pandemic has caused that plan to be postponed; we're now planning gala concerts to be held there—my home church, whose wonderful organ inspired much of this music— on October 20 and 21, 2023.

Are parts of the work available for watching or listening?

When I was in the midst of writing Fantasia Apocalyptica, my friend Jin Kyung Lim performed an early version of Chapter 6 as part of a recital that she gave on the Murray Harris organ at Stanford's Memorial Church (04 November 2015). Chapter 6 begins with the “Four Horsemen of the Apocalypse” and ends with a terrifying earthquake. (view Tim Davis's artwork based on this recording)

The video at the top of this page includes excerpts from Chapter 21, “The New Jerusalem”, with Jan Overduin's explanations of the background underlying this music.

Here are audio files captured at the première performance in Studio Acusticum:

And here's Jan Overduin's improvisation on Now, which he played just before the Fantasia at the première.

By the way, here's a snapshot of that performance, as seen by the audience when the saints from Judah came marchin’ in. (Photo by Sagar Savla.)

And why stop there? Videos of the entire world première performance are now available on YouTube, accessible either in 3D or 2D. You can watch one chapter at a time, or schedule all 22 chapters to be streamed, etc.

Furthermore, there's a superbly edited YouTube video of the North American première performance — surely the best presentation so far of this multimedia work — thanks to the Pascal Lectures Committee of the University of Waterloo. Isaac Morland's video tracks used in that performance can be downloaded here: screen1–art; screen2–texts.

The Czech première performance by Jan Rotrekl has also been captured and edited brilliantly — quite fascinating to watch, because a Czech translation has been added to the Greek and English texts.

Parts of this work have even been recorded on the 16-rank organ in my home: Chapter 1 Chapter 2 Chapter 3 Chapter 12 Chapter 21 Chapter 22

One curiosity is the recording of Chapter 15 that Overduin made when visiting the Internet Archive in April 2017. (We were considering the possibility of having the San Francisco première there, but that organ doesn't have enough memory for changes of registration.)

It's especially interesting to hear parts of it played also on the famous van Hagerbeer Organ in the Pieterskerk, Leiden. This organ (built circa 1640) reportedly contains more 15th-century pipes than any other organ in the world. It was certainly not designed for music such as this, because the organs of those days had many fewer notes; and its mean-tone tuning was naturally optimized for pre-Bach works. But “to those who have ears to hear, let them hear”! Chapter 2; Chapter 20; Chapter 21:1–4. (These fascinating experiments were made in the spring of 2019 by Jan Overduin. Since he recorded the audio at the console, the Rueckpositiv (controlled by the lowest keyboard) sounds louder than the Hauptwerk and the Bovenwerk.)

Jan Overduin has artfully combined the music from the première performance with the original handwritten manuscript, in a sequence of seven videos: Playlist for all seven

And to top that, he's also combined the music with Duane Bibby's awesome illustrations, and with selected Bible texts, so that you can see them up close as you watch and listen: Playlist for all seven

The US première, on the Ruffati organ at the Cathedral of St. Mary of the Assumption in San Francisco, was livestreamed in December 2021 and can be viewed here: (Chapters 1–12) (Chapters 13–22)

I'll collect links to other performances and post them here when I learn about them.

Published references

Acknowledgments

I've received fantastic help on this fantasy from so many people that, alas, I can't remember all of their names. I do want to give special thanks here to individuals who have voluntarily contributed truly extraordinary amounts of their own time:
Michael Angeletti, who masterminded the digital archiving of the video and audio recordings and made them publicly accessible in convenient form;
Anders Björner, who orchestrated several trips to Sweden related to this project;
Patrick Brunet, who masterfully combined audio and video to capture the exciting North American première performance, as well as the associated public lectures mentioned above;
Carson Cooman, who gave encouragement and good advice at an early stage;
Brian Grady, Liza Patnoe, Ray Tarara, and Sagar Savla from Google, who expertly captured the première performance with state-of-the-art 360-degree cameras and a drone;
Anders Hannus, who expertly recorded the première performance in 24-bit 96kHz “surround sound”, using special microphones;
Yoichi Hariguchi, for immense technical help with the video displays in the California premières;
Lars Johansson and Magnus Grönberg, who masterminded the staging, lighting, and video mixing at the première;
Jin Kyung Lim, who gave the first performances and provided me with significant feedback, beginning when I'd written only about 1/3 of the music—and later played the US première;
Svante Linusson and Arnfinn Röste, who flew with me when I first visited the Music College in Piteå, Sweden;
Stephen Malinowski, who converted my handwritten manuscript into a beautifully typeset document, and has been planning video track #4;
Isaac Morland, who organized, simplified, and improved video tracks #1 and #2;
Jan Overduin, an “early adopter” who immediately understood my goals, then became my partner in refining the score, and brilliantly interpreted it on Organ Acusticum as well as the First United Kney organ at its première performances in 2018;
Craig Sapp, who has been teaching me everything that I need to know about music software and hardware;
Petr Sojka, who produced the marvelous video of the Czech première with the help of computer wizardry by Vít Novotný and Tomáš Szaniszlo;
Gary Verkade and Kari Engesnes, who pioneered the “playing” of video tracks #1 and #3.

Details

Music scores to download

Here are the latest performance-oriented scores for the complete work, as of 04 March 2019. I've also included scans of my original handwritten manuscript, as it existed on 16 September 2016, in case you want to psych out what I had in mind as I was formulating the music.

Note: These PDF files are designed to work best on 11×17 (ledger size) paper, if your printer supports it.

Page 1 (title, and registration hints)
(the opening page)
Chapter 1: Introduction
(typeset score) (handwritten MS)
Chapter 2: Letters to Ephesus, Smyrna, Pergamum, Thyatira
(typeset score) (handwritten MS)
Chapter 3: Letters to Sardis, Philadelphia, Laodicea
(typeset score) (handwritten MS)
Chapter 4: The heavenly throne
(typeset score) (handwritten MS)
Chapter 5: The scroll and the Lamb
(typeset score) (handwritten MS)
Chapter 6: Four horsemen; open seals
(typeset score) (handwritten MS)
Chapter 7: Saints marching in
(typeset score) (handwritten MS)
Chapter 8: Four trumpets
(typeset score) (handwritten MS)
Chapter 9: Trumpets and woes
(typeset score) (handwritten MS)
Chapter 10: The sweet and sour little scroll
(typeset score) (handwritten MS)
Chapter 11: Seventh trumpet; open temple
(typeset score) (handwritten MS)
Chapter 12: The woman and the dragon
(typeset score) (handwritten MS)
Chapter 13: The blasphemous beast; 666
(typeset score) (handwritten MS)
Chapter 14: God's harvest
(typeset score) (handwritten MS)
Chapter 15: Preparing seven plagues
(typeset score) (handwritten MS)
Chapter 16: Bowls of wrath; Armageddon
(typeset score) (handwritten MS)
Chapter 17: The prostitute
(typeset score) (handwritten MS)
Chapter 18: Babylon is fallen
(typeset score) (handwritten MS)
Chapter 19: Hallelujah! Hallelujah!
(typeset score) (handwritten MS)
Chapter 20: The thousand years
(typeset score) (handwritten MS)
Chapter 21: The new Jerusalem
(typeset score) (handwritten MS)
Chapter 22: The coming Messiah
(typeset score) (handwritten MS)

Video track details

If you're planning a complete performance, here are some hints about how to control the accompanying video tracks.

Some tentative registrations

I mentioned above that this piece is “devilishly difficult” to play in its entirety at one sitting. However, the individual chapters are each approachable, and the notes themselves are not particularly challenging. Difficulties arise primarily because the music uses frequent changes of registration in order to match Revelation's dramatic developments.

I wanted to make sure that this music could be performed adequately on medium-size organs, as well as world-class instruments such as Organ Acusticum. So I carried out detailed experiments on the two-manual Casavant organ at First Lutheran Church in Palo Alto, where I used general pistons on eight levels of that organ's memory. Here are complete details of the Casavant registrations.

For the record, here also are complete details of the Woehl registrations that I used when recording Chapter 1 at Studio Acusticum in January 2017, as well as some ideas for Woehl registrations in the other chapters. (Jan Overduin made significant improvements later.)

A performance note

From a musical standpoint, it would be better to append the first two measures of Chapter 16 to the end of Chapter 15, and to delete them from Chapter 16. From a theological standpoint, one could also argue that it would have been better if the Biblical scholars who divided Revelation into chapters long ago had chosen to make Chapter 15 one verse longer than they did (so that 16:1 would be 15:9 and 16:2 would be 16:1, and so on). I've preserved the traditional numbering; but a performer may well prefer to make a more logical break between those chapters.

Dictionary of motifs

Here's a complete dictionary of the Greek textual motifs used and the musical equivalents that I chose. (If that page doesn't display Greek letters, set your browser's default encoding to Unicode (UTF-8).)

And here's an inverse dictionary, showing verse-by-verse which textual motifs were translated.

Also a list of special effects.

Allusions to existing music

Fantasia Apocalyptica pays homage to dozens of other musical works, enumerated here.

Errata

Finally, here's a list of changes made to the score since 08 February 2017.

Don Knuth's home page

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