APA (7e ed.) Bronvermelding

Beckman, T. N., & Bartels, R. (1955). Credits and collections in theory and practice (6th ed.). McGraw-Hill.

Chicago (17e ed.) Bronvermelding

Beckman, Theodore N., en Robert Bartels. Credits and Collections in Theory and Practice. 6th ed. N.Y.: McGraw-Hill, 1955.

MLA (8e ed.) Bronvermelding

Beckman, Theodore N., en Robert Bartels. Credits and Collections in Theory and Practice. 6th ed. McGraw-Hill, 1955.