1. Hetland S, Martinsen I, Radzuk B, Thomassen Y (1991) Anal Sci 7:1029
2. Quevauviller P, Maier EA, Griepink B (1992) Acta (in press)
3. Wells DE, De Boer J, Tuinstra LGMT, Reutergardh L, Griepink B (1988) Fresenius Z Anal Chem 332:591
4. Ure A, Quevauviller P, Muntau H, Griepink B (1992) EUR Report, CEC Brussels (in press)
5. Ure A, Quevauviller P, Muntau H, Griepink B (1993) Int J Environ Anal Chem (in press)