Heardman, h. (1987). Melahirkan secara alamiah (A way to natural childbirth). EGC.
Cita Chicago (17th ed.)Heardman, helen. Melahirkan Secara Alamiah (A Way to Natural Childbirth). EGC, 1987.
Cita MLA (9th ed.)Heardman, helen. Melahirkan Secara Alamiah (A Way to Natural Childbirth). EGC, 1987.
Atenció: Aquestes cites poden no estar 100% correctes.