Gaya APA

Spiro, R, L. et al (2008). Management of a sales force twelfth edition (Twelfth edition). Boston: McGraw-Hill/Irwin.

Gaya MLA

Spiro, Rosann, L.. et al. "Management of a sales force twelfth edition". Twelfth edition Boston: McGraw-Hill/Irwin, 2008. MM.