Международная сертификация предметов коллекционирования NGC
The Certified Collectibles Group ;
2:06 Numismatic Guaranty Corporation NGC
4:21 Numismatic Conservation Services (NCS)
5:33 Paper Money Guaranty (PMG)
7:38 Certified Guaranty Company (CGC)
5:58 Classic Collectible Services (CCS)
11:18 Authenticated Stamp Guaranty (ASG)
American Numismatic Association
Professional Numismatists Guild