APA aipamena

FREEMANTLE, D. (1992). Incredible Customer Service. McGraw-Hill.

Chicago Style aipamena

FREEMANTLE, David. Incredible Customer Service. McGraw-Hill, 1992.

MLA aipamena

FREEMANTLE, David. Incredible Customer Service. McGraw-Hill, 1992.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.