| Prüfer | Art der Urkunde | Katalog | KatalogNr. |
|---|
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 1; 4 a |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 4; 3 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 7 b; 7 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 20 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 42 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 43 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | D 44 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 44 - 53 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 52 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 52 |
| The Philatelic Foundation, (Prüferkommission) | Attest | Stanley Gibbons | 191 |
| The Stamp Trade Protection, Association Ltd. (Prüferkommission) | Attest | Stanley Gibbons | 38 c |
| Todd, Gregory (AIEP (Association internationale des experts en philatélie)) | Attest | Stanley Gibbons | 3; 4 |
| Toselli, Roberto (Sonstiges) | Attest | Stanley Gibbons | 1 |
| Wallner, Ferdinand (AIEP (Association internationale des experts en philatélie)) | Attest | Stanley Gibbons | 40 |
| Warwick & Warwick, Philatelic Investment Service (Händlergarantien) | Attest | Stanley Gibbons | 4 |
| Warwick & Warwick, Philatelic Investment Service (Händlergarantien) | Attest | Stanley Gibbons | 5 |
| Wigmore, Michael (Sonstiges) | Attest | Stanley Gibbons | 155 a |
| Williams, Mike (Sonstiges) | Attest | Stanley Gibbons | C 3 |
| Williams, Mike (Sonstiges) | Attest | Stanley Gibbons | C 7 |
| Williams, Mike (Sonstiges) | Attest | Stanley Gibbons | C 7 |
| Williams, Mike (Sonstiges) | Attest | Stanley Gibbons | C 9 |
| Williams, Mike (Sonstiges) | Attest | Stanley Gibbons | 21 |
| Zumstein, Cie (Händlergarantien) | Attest | Stanley Gibbons | 14 |
