APA Citation

Thonson, F. G. Four species of land snails from Costa Rica and Panamá (Pulmonata Spiraxidae).

Chicago Style Citation

Thonson, Freed G. Four Species of Land Snails From Costa Rica and Panamá (Pulmonata Spiraxidae).

MLA Citation

Thonson, Freed G. Four Species of Land Snails From Costa Rica and Panamá (Pulmonata Spiraxidae).

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