Cita APA (7th ed.)
Knirr, J. (1881). Das rechtwinklige rationale Dreieck.
Cita Chicago (17th ed.)
Knirr, Josef. Das Rechtwinklige Rationale Dreieck. Wien, 1881.
Cita MLA (9th ed.)
Knirr, Josef. Das Rechtwinklige Rationale Dreieck. 1881.
Atenció: Aquestes cites poden no estar 100% correctes.