APA (7th ed.) Citation

Ptolemy, a. 2. c., & Toomer, G. J. (1984). Ptolemy's Almagest. Springer-Verlag.

Chicago Style (17th ed.) Citation

Ptolemy, active 2nd century, and G. J. Toomer. Ptolemy's Almagest. New York: Springer-Verlag, 1984.

MLA (9th ed.) Citation

Ptolemy, active 2nd century, and G. J. Toomer. Ptolemy's Almagest. Springer-Verlag, 1984.