@book{27386,
	author = {Visser, D. J. L.},
	title = {The ochre deposits of the Riversdale district,},
	publisher = {Government printer,},
	year = {1937.},
	series = {South Africa. [Geological Survey] Geological series. Bulletin},
	address = {Pretoria,},
	note = {At head of title: ... Union of South Africa. Department of mines.}
}