APA aipamena

Schuller ,Robert H. (1988). Tough Times Never Last But Tough People Do. Orient Paperbacks.

Chicago Style aipamena

Schuller ,Robert H. Tough Times Never Last But Tough People Do. Delhi: Orient Paperbacks, 1988.

MLA aipamena

Schuller ,Robert H. Tough Times Never Last But Tough People Do. Orient Paperbacks, 1988.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.