Osborn, H. F. (1924). Psittacosaurus and Protiguanodon: Two Lower Cretaceous iguanodonts from Mongolia.
Chicago Style (17th ed.) CitationOsborn, Henry Fairfield. Psittacosaurus and Protiguanodon: Two Lower Cretaceous Iguanodonts from Mongolia. New York, N.Y, 1924.
MLA (9th ed.) CitationOsborn, Henry Fairfield. Psittacosaurus and Protiguanodon: Two Lower Cretaceous Iguanodonts from Mongolia. 1924.
Warning: These citations may not always be 100% accurate.