De Leon, H. S., & De Leon, H. M. (2001). Comments and cases on sales (4th ed.). Published & distributed by Rex Book Store.
Chicago-referens (17:e uppl.)De Leon, Hector S., och Hector M. De Leon. Comments and Cases on Sales. 4th ed. Manila, Philippines: Published & distributed by Rex Book Store, 2001.
MLA-referens (9:e uppl.)De Leon, Hector S., och Hector M. De Leon. Comments and Cases on Sales. 4th ed. Published & distributed by Rex Book Store, 2001.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.