Cita APA (7th ed.)
Roberts, D. D. (1973). The existential graphs of Charles S. Peirce. Mouton.
Cita Chicago (17th ed.)
Roberts, Don D. The Existential Graphs of Charles S. Peirce. The Hague: Mouton, 1973.
Cita MLA (9th ed.)
Roberts, Don D. The Existential Graphs of Charles S. Peirce. Mouton, 1973.
Atenció: Aquestes cites poden no estar 100% correctes.