| Year | Club / Magazine | Country, code | Homepage |
| 1961 | Quarter Advertiser ¤ March 22 1961 - volume 15 number 10
  | US | |
| 1965 | Kumaripenpals & Stamp | NEPAL | |
| 1967 | Independent Publications Network
  | US | |
| 1968 | Underground Press Syndicate Directory
 | US | |
| 1969 | Mail Trader
  | US | |
| 1970 | The International Collector's Directory | US | |
| 1971 | Classified Ads
 | US | |
| 1975 | | 0021 | love |
| 1976 | The Publishers Manual
 | US | |
| 1977 | Bookseller's Portfolio
 | US | |
| 1977 | Hot Sheet - giant MO magazine - and The Money Three
  | US | |
| 1977 | Jack Willis | CANADA | |
| 1977 | O. E. Emby's Directory of Publishers
 | US | www.penpalclubs.net/1977modirectoryofpublishers.htm |
| 1978 | Trade Market News
 | CA | |
| 1978 | World Trade Opportunities
 | US | |
| 1979 | 5M International News
 | SG | |
| 1979 | Book on Penfriendship by Piare Lal Sharma | IN | |
| 1979 | Pen Pal
 | CH | |
| 1979 | Prime Sources & Circular Mailers
  | US | |
| 1979 | Selective Advertising Services | US | |
