@book{4190,
	author = {Nygren, M.},
	title = {Quality assessment of PCB, PCDD and PCDF analysis : third round of WHO-coordinated study.},
	publisher = {WHO Regional Office for Europe,},
	year = {1995.},
	series = {(Environemtal health in Europe ; no. 2).},
	address = {Copenhagen : }
}