@book{5283,
	author = {Sachs, I (Ed.)},
	title = {Main trends in economics},
	publisher = {George Allen and Unwin},
	year = {1973},
	address = {London},
	note = {This essays was originally published as chapter 4 in "Main trends of research in the social and human science", part I, Mouton/Unesco 1970}
}