Cita APA (7a ed.)

Ptolemeu, C., Copernicus, N., Kepler, J., Taliaferro, R. C., & Wallis, C. G. (1952). The Almagest. Encyclopaedia Britannica.

Cita Chicago Style (17a ed.)

Ptolemeu, Claudi, Nicolaus Copernicus, Johannes Kepler, R. Catesby Taliaferro, y Charles Glenn Wallis. The Almagest. Chicago [etc.]: Encyclopaedia Britannica, 1952.

Cita MLA (9a ed.)

Ptolemeu, Claudi, et al. The Almagest. Encyclopaedia Britannica, 1952.