APA (7th ed.) Citation

Gould, J. (1850). Buffon's skua (Stercorarius parasiticus) [picture]. [185-?].

Chicago Style (17th ed.) Citation

Gould, John. Buffon's Skua (Stercorarius Parasiticus) [picture]. [185-?], 1850.

MLA (9th ed.) Citation

Gould, John. Buffon's Skua (Stercorarius Parasiticus) [picture]. [185-?], 1850.

Warning: These citations may not always be 100% accurate.