@book{28277,
	author = {Van Zyl, J. S. and South Africa.},
	title = {Magnesite in the Union of South Africa /},
	publisher = {Govt. Printer,},
	year = {1942.},
	series = {Geological Survey memoir ;},
	address = {Pretoria :},
	note = {At head of title: Union of South Africa. Dept. of Mines.}
}