APA (7e ed.) Bronvermelding

Kauffmann, R. M., Read, T. T., & Zettl, A. (1977). The deficiency index problem for powers of ordinary differential expressions. Springer-Verlag.

Chicago (17e ed.) Bronvermelding

Kauffmann, Robert M., Thomas T. Read, en Anton Zettl. The Deficiency Index Problem for Powers of Ordinary Differential Expressions. Berlín: Springer-Verlag, 1977.

MLA (9e ed.) Bronvermelding

Kauffmann, Robert M., et al. The Deficiency Index Problem for Powers of Ordinary Differential Expressions. Springer-Verlag, 1977.