Cita APA (7th ed.)

Juan XXI, P. (1972). Tractatus: Called afterwards Summule Logicales. Van Gorcum.

Cita Chicago (17th ed.)

Juan XXI, Papa. Tractatus: Called Afterwards Summule Logicales. Assen: Van Gorcum, 1972.

Cita MLA (9th ed.)

Juan XXI, Papa. Tractatus: Called Afterwards Summule Logicales. Van Gorcum, 1972.