Cita APA (7a ed.)

Helgi Guðmundsson, Hlíðerg, J. B., & Yates, A. (1997). Birdwatching. Ritsmiðjan.

Cita Chicago Style (17a ed.)

Helgi Guðmundsson, Jón Baldur Hlíðerg, y Anna Yates. Birdwatching. Reykjavik: Ritsmiðjan, 1997.

Cita MLA (9a ed.)

Helgi Guðmundsson, et al. Birdwatching. Ritsmiðjan, 1997.