Παραπομπή APA

Portman-graham r. (1975). Mating and whelping of dogs (3.). London.

Παραπομπή Chicago Style

Portman-graham r. Mating and Whelping of Dogs. 3. London, 1975.

Παραπομπή MLA

Portman-graham r. Mating and Whelping of Dogs. 3. London, 1975.