1. Armitage P (1971) Statistical methods in medical research. Blackwell Scientific, Oxford
2. Bjørseth A, Bjórseth O, Fjeldstad PE (1981) Polycyclic aromatic hydrocarbons in the work atmosphere. Scand J Work Environ Health 7:223?232
3. Hansen ÅM, Olsen IB, Holst E, Poulsen OM (1991) Validation of an improved high-performance liquid chromatography/fluorescence detection method for the simultaneous quantification of 15 different polycyclic aromatic hydrocarbons. Ann Occup Hyg (in press)
4. International Agency for Research on Cancer (1983?1985) Monographs on the evaluation of the carcinogenic risk of chemicals to humans, vol 32?35. IARC, Lyon, France
5. Lindstedt G, Sollenberg J (1982) Polycyclic aromatic hydrocarbons in the occupational environment. Scand J Work Environ Health 8:1?19