Webber, R. T., & Johnson, R. H. (1993). Buying and supplying quality. Tata McGraw Hill.
Chicago Style aipamenaWebber, Richard T., and Ross H. Johnson. Buying and Supplying Quality. New Delhi: Tata McGraw Hill, 1993.
MLA aipamenaWebber, Richard T., and Ross H. Johnson. Buying and Supplying Quality. Tata McGraw Hill, 1993.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.