APA aipamena

Helfert, E. A. (1972). Techniques of. Dow Jones - Irwin.

Chicago Style aipamena

Helfert, Enrich A. Techniques of. Illinios: Dow Jones - Irwin, 1972.

MLA aipamena

Helfert, Enrich A. Techniques of. Dow Jones - Irwin, 1972.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.