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5 Reasons Why Sony's Universal Media Disc Failed
Universal Media Disc - Wikipedia
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File:Universal Media Disc, Minidisc and Compact Cassette - size comparison.jpg - Wikimedia Commons
Preservation Self-Assessment Program (PSAP) | Optical Media
Preservation Self-Assessment Program (PSAP) | Optical Media
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5 Reasons Why Sony's Universal Media Disc Failed
How to Tell if a Disc Is a CD or a DVD: 7 Steps (with Pictures)
Amazon.com: M-DISC 4.7GB DVD+R Permanent Data Archival Backup Blank Disc Media - 50 Pack : Electronics
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2) PSP UMD UNIVERSAL MEDIA DISCS & CASE with MOVIES- Superbad & Snatch | eBay
Universal Media Disc | Article about Universal Media Disc by The Free Dictionary
