APA

Townsend C. H., .Birds from Cocos and Malpelo Islands: with notes on petrels obtained at sea. : .

Chicago

Townsend C H, .Birds from Cocos and Malpelo Islands: with notes on petrels obtained at sea. : .

Harvard

Townsend C. H., .Birds from Cocos and Malpelo Islands: with notes on petrels obtained at sea. : .

MLA

Townsend C H, .: . .