APA (7th ed.) Citation

Frank, P. (1943). Relativity and its astronomical implications. Sky publishing corporation, Harvard college observatory.

Chicago Style (17th ed.) Citation

Frank, Philipp. Relativity and Its Astronomical Implications. Cambridge, Mass.: Sky publishing corporation, Harvard college observatory, 1943.

MLA (9th ed.) Citation

Frank, Philipp. Relativity and Its Astronomical Implications. Sky publishing corporation, Harvard college observatory, 1943.