Cita APA

Helen, Helen Mellanby, & Helen Mellanby. (1953). Animal life in freshwater (5.). London.

Citación estilo Chicago

Helen, Helen Mellanby, and Helen Mellanby. Animal Life in Freshwater. 5. London, 1953.

Cita MLA

Helen, et al. Animal Life in Freshwater. 5. London, 1953.