Não informado. (1970). Working paper series. National Bureau of Economic Research.
Chicago-Zitierstil (17. Ausg.)Não informado. Working Paper Series. Cambridge, Mass: National Bureau of Economic Research, 1970.
MLA-Zitierstil (8. Ausg.)Não informado. Working Paper Series. National Bureau of Economic Research, 1970.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.