Gaya APA
Futrell, C. (2002).
Fundamentals of selling customers for life (ed.7).
United States Of America:
Irwin Mcgraw-Hill.
Gaya MLA
Futrell, Charles.
"Fundamentals of selling customers for life".
ed.7
United States Of America:
Irwin Mcgraw-Hill,
2002.
Teks.