Gaya APA

Samuelson, P, A., Nordhaus, W, D. (1992). Economics Fourteenth edition (Fourteenth edition). Singapore: McGraw-Hill. inc.

Gaya MLA

Samuelson, Paul, A.., Nordhaus, William, D.. "Economics Fourteenth edition". Fourteenth edition Singapore: McGraw-Hill. inc, 1992. Textbook.