Hille, H. (1968). moderne philatelie. Transpress.
Lua i Stíl Chicago (17ú heag.)Hille, Horst. Moderne Philatelie. Berlin: Transpress, 1968.
Lua MLA (8ú heag.)Hille, Horst. Moderne Philatelie. Transpress, 1968.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.