Cita APA (7a ed.)

Vatican Philatelic Society, Ufficio Philatelico e Numismatico, & Etchingham, J. Vatican stamp collection.

Cita Chicago Style (17a ed.)

Vatican Philatelic Society, Ufficio Philatelico e Numismatico, y John Etchingham. Vatican Stamp Collection.

Cita MLA (8a ed.)

Vatican Philatelic Society, et al. Vatican Stamp Collection.