Hille, H. (1968). moderne philatelie. Transpress.
Cita Chicago (17th ed.)Hille, Horst. Moderne Philatelie. Berlin: Transpress, 1968.
Cita MLA (8th ed.)Hille, Horst. Moderne Philatelie. Transpress, 1968.
Atenció: Aquestes cites poden no estar 100% correctes.