Gaya APA
Douglas, E, J. (1992).
Managerial economics : analysis and strategy ed. 4 (4).
St.Paul:
Prentice Hall International.
Gaya MLA
Douglas, Evan, J..
"Managerial economics : analysis and strategy ed. 4".
4
St.Paul:
Prentice Hall International,
1992.
Text.