Não informado. (1935). Drama of the skies. American Museum of Natural History, Hayden Planetarium.
Chicago-viite (17. p.)Não informado. Drama of the Skies. New York: American Museum of Natural History, Hayden Planetarium, 1935.
MLA-viite (8. p.)Não informado. Drama of the Skies. American Museum of Natural History, Hayden Planetarium, 1935.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.