| EFM, Expertización Filatélica de Madrid (Prüferkommission) |
Attest |
Edifil |
90 |
| RPSL, Royal Philatelic Society (Prüferkommission) |
Attest |
Stanley Gibbons |
90 - 92 |
| Brandon, David Expert Committee (Prüferkommission) |
Attest |
Stanley Gibbons |
90 b |
| Indian States Expertizing Service Inc., (ISES) (Prüferkommission) |
Attest |
Stanley Gibbons |
92 |
| Raybaudi, Experts (Prüferkommission) |
Attest |
Sassone |
921 |
| Deutsches Institut, für internationale Philatelie (Prüferkommission) |
Prüfermitteilung |
Michel |
921 U |
| Brandon, David Expert Committee (Prüferkommission) |
Attest |
Scott |
93 |
| APS, (American Philatelic Society) (Prüferkommission) |
Attest |
Scott |
93 |
