Cita APA (7th ed.)

Heuvelmans, B. (1959). On the track of unknown animals. Hill and Wang.

Cita Chicago (17th ed.)

Heuvelmans, Bernard. On the Track of Unknown Animals. Nueva York: Hill and Wang, 1959.

Cita MLA (9th ed.)

Heuvelmans, Bernard. On the Track of Unknown Animals. Hill and Wang, 1959.