@book{27632,
	author = {Schwellnus, C. M.},
	title = {Vermiculite deposits in the Palaboroa area, N. E. Transvaal,},
	publisher = {The Government Printer,},
	year = {1938.},
	series = {South Africa. Geological Survey. Geological series. Bulletin},
	address = {Pretoria,},
	note = {At head of title: ... Union of South Africa.  Department of Mines.}
}