APA (7th ed.) Citation

British Museum (Natural History). Department of Botany, Ramsbottom, J., & Smith, W. G. A handbook of the larger British fungi.

Chicago Style (17th ed.) Citation

British Museum (Natural History). Department of Botany, John Ramsbottom, and Worthington George Smith. A Handbook of the Larger British Fungi.

MLA (9th ed.) Citation

British Museum (Natural History). Department of Botany, et al. A Handbook of the Larger British Fungi.