Hass, K. (1969). Creative salesmanship understanding essentials. George Press.
Chicago Style aipamenaHass, K. Creative Salesmanship Understanding Essentials. London: George Press, 1969.
MLA aipamenaHass, K. Creative Salesmanship Understanding Essentials. George Press, 1969.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.