Não informado. (1911). Contributions from the Princeton University Observatory. Princeton University Observatory.
Cita Chicago Style (17a ed.)Não informado. Contributions from the Princeton University Observatory. Princeton, NJ: Princeton University Observatory, 1911.
Cita MLA (8a ed.)Não informado. Contributions from the Princeton University Observatory. Princeton University Observatory, 1911.
Precaución: Estas citas no son 100% exactas.