Παραπομπή APA

Willoughby, L. G. (1976). Freshwater biology. Hutchinson.

Παραπομπή Chicago Style

Willoughby, L. G. Freshwater Biology. London: Hutchinson, 1976.

Παραπομπή MLA

Willoughby, L. G. Freshwater Biology. Hutchinson, 1976.