| Raybaudi, Experts (Prüferkommission) |
Attest |
Sassone |
585/IV |
| APS, (American Philatelic Society) (Prüferkommission) |
Attest |
Michel |
59 |
| BPA, Expertising Limited (Prüferkommission) |
Attest |
Stanley Gibbons |
59 a |
| RPSL, Royal Philatelic Society (Prüferkommission) |
Attest |
Stanley Gibbons |
59 a |
| The Philatelic Foundation, (Prüferkommission) |
Attest |
Scott |
59 L 2 b |
| PSE, Professional Stamp Experts (Prüferkommission) |
Sonstiges |
Scott |
594 |
| The American Philatelic, Expertization Service (Prüferkommission) |
Attest |
Scott |
5a |
| RPSL, Royal Philatelic Society (Prüferkommission) |
Attest |
Stanley Gibbons |
5b |
