@book{15512,
	author = {Golterman, H. L. and Clymo, R. S,},
	title = {Methods for chemical analysis of fresh waters /},
	publisher = {Blackwell Scientific,},
	year = {1969.},
	series = {International Biological Programme. IBP handbook ;},
	address = {Oxford :},
	note = {Includes index.}
}