APA
Samuelson P. A., Nordhaus W., . (1998). Economics. New York: Tata MacGraw-Hill.
Chicago
Samuelson P A, Nordhaus W, . 1998. Economics. New York: Tata MacGraw-Hill.
Harvard
Samuelson P. A., Nordhaus W., . (1998). Economics. New York: Tata MacGraw-Hill.
MLA
Samuelson P A, Nordhaus W, . Economics. New York: Tata MacGraw-Hill. 1998.
