Hawkins, A. (1997). The improving profitability pocketbook. Management Pocketbooks.
Chicago Style aipamenaHawkins, Anne. The Improving Profitability Pocketbook. Hants, U.K: Management Pocketbooks, 1997.
MLA aipamenaHawkins, Anne. The Improving Profitability Pocketbook. Management Pocketbooks, 1997.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.