Heppenstall, R. (1968). The connecting door. Dufour.
Cita Chicago (17th ed.)Heppenstall, Rayner. The Connecting Door. [Chester Springs, Pa.]: Dufour, 1968.
Cita MLA (9th ed.)Heppenstall, Rayner. The Connecting Door. Dufour, 1968.
Atenció: Aquestes cites poden no estar 100% correctes.