Crosby, P. B. (2004). Quality without Tears. Orient BlackSwan.
Dyfyniad Arddull ChicagoCrosby, Philip B. Quality Without Tears. New Delhi: Orient BlackSwan, 2004.
Dyfyniad MLACrosby, Philip B. Quality Without Tears. Orient BlackSwan, 2004.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.