@book{21315,
	author = {Marais, W.J.},
	title = {Natuur- en skeikunde vir standerds IX en X /},
	publisher = {Nasionale Boekhandel,},
	year = {[19--]},
	address = {Kaapstad :},
	edition = {Sesde druk},
	note = {Bladwyser: p416-420}
}