Gaya APA
Lipsey, R, G. (1979).
An Introduction To Positive Economics (fifth edition 1979).
London:
Weidenfeld And Nicolson, London.
Gaya MLA
Lipsey, Richard, G..
"An Introduction To Positive Economics".
fifth edition 1979
London:
Weidenfeld And Nicolson, London,
1979.
Text.