Cruz, V. J. F. (1991). A Study of a purchasing system. College of Engineering.
Citazione stile Chigago Style (17a edizione)Cruz, Victoria Jocelyn F. A Study of a Purchasing System. Diliman, Quezon City: College of Engineering, 1991.
Citatione MLA (9a ed.)Cruz, Victoria Jocelyn F. A Study of a Purchasing System. College of Engineering, 1991.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.