Não informado. (1953). Contributions from the Perkins Observatory. Ohio State University, Ohio Wesleyan University.
Cita Chicago Style (17a ed.)Não informado. Contributions from the Perkins Observatory. Delaware, Ohio: Ohio State University, Ohio Wesleyan University, 1953.
Cita MLA (8a ed.)Não informado. Contributions from the Perkins Observatory. Ohio State University, Ohio Wesleyan University, 1953.
Precaución: Estas citas no son 100% exactas.