Παραπομπή APA

Billings, M. (1972). Structural Geology. Prentice-Hall of India.

Παραπομπή Chicago Style

Billings, Marland.P. Structural Geology. Delhi: Prentice-Hall of India, 1972.

Παραπομπή MLA

Billings, Marland.P. Structural Geology. Prentice-Hall of India, 1972.