| Auteur(s) | Année | Titre | Publication | Volume | |
|---|---|---|---|---|---|
| Clarke (), Sheppard (P. M.) | 1956 | A further report on the genetics of the machaon group of Swallowtail Butterflies | Evolution | 10 | |
| Clarke (), Sheppard (P. M.) | 1956 | The breeding in captivity of the hybrid Swallowtail Papilio machaon gorganus Fruhstorfer male ×Papilio hospiton Gené femelle | The Entomologist | 88 (1111) | |
| Clarke (), Sheppard (P. M.) | 1955 | A preliminary report on the genetics of the machaon group of Swallowtail Butterflies | Evolution | 9 |