APA

Beckwith R. H., . (211934). Contribultions to the geology of northern Mongolia. New York: American Museum of Natural History.

Chicago

Beckwith Radcliffe H, . 211934. Contribultions to the geology of northern Mongolia. New York: American Museum of Natural History.

Harvard

Beckwith R. H., . (211934). Contribultions to the geology of northern Mongolia. New York: American Museum of Natural History.

MLA

Beckwith Radcliffe H, . Contribultions to the geology of northern Mongolia. New York: American Museum of Natural History. 211934.