APA

Ridgway R., . (1894). Descriptions of twenty-two new species of birds from the Galapagos Islands. : .

Chicago

Ridgway R, . 1894. Descriptions of twenty-two new species of birds from the Galapagos Islands. : .

Harvard

Ridgway R., . (1894). Descriptions of twenty-two new species of birds from the Galapagos Islands. : .

MLA

Ridgway R, . Descriptions of twenty-two new species of birds from the Galapagos Islands. : . 1894.