Duffy, P. (1994). Business to Business marketing. Vision.
Chicago-čujuhus (17. p.)Duffy, Philip. Business to Business Marketing. Delhi: Vision, 1994.
MLA-čujuhus (9. p.)Duffy, Philip. Business to Business Marketing. Vision, 1994.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.