APA

Oberholser H. C., .Catalogue of a collection of hummingbirds from Ecuador and Colombia. : .

Chicago

Oberholser Harry C, .Catalogue of a collection of hummingbirds from Ecuador and Colombia. : .

Harvard

Oberholser H. C., .Catalogue of a collection of hummingbirds from Ecuador and Colombia. : .

MLA

Oberholser Harry C, .: . .