Gaya APA
Friedman, M., Friedman, R. (1980).
Free to choose : a personal statement .
San Diego:
Harcourt Brace Jovanovich Publishers.
Gaya MLA
Friedman, Milton., Friedman, Rose.
"Free to choose : a personal statement".
San Diego:
Harcourt Brace Jovanovich Publishers,
1980.
Text.