Παραπομπή APA

Goldstein, A. (1992). Secrets of overcoming sales resistance (7.).

Παραπομπή Chicago Style

Goldstein, Albert. Secrets of Overcoming Sales Resistance. 7. :, 1992.

Παραπομπή MLA

Goldstein, Albert. Secrets of Overcoming Sales Resistance. 7. 1992.