@book{9312,
	author = {University of the Witwatersrand},
	title = {Group and semigroup rings: proceedings of the international conference on group and semigroup rings},
	publisher = {University of Witwatersrand},
	year = {1985},
	series = {North-Holland mathematics studies},
	address = {Johannesbrug},
	note = {aInternational conference on group and semigroup and rings(1985: University of the Witwatersrand}
}