Cita APA (7th ed.)
Byerly, W. E. Introduction to the Calculus of Variations. Harvard University.
Cita Chicago (17th ed.)
Byerly, William Elwood. Introduction to the Calculus of Variations. Cambridge, EUA: Harvard University.
Cita MLA (9th ed.)
Byerly, William Elwood. Introduction to the Calculus of Variations. Harvard University.
Atenció: Aquestes cites poden no estar 100% correctes.