1. Houk RS, Fassel VA, Flesch GD, Svec HJ, Gray AL, Taylor CE (1980) Analyst 52:2283?2289
2. Hieftje GM, Vickers GH (1989) Anal Chim Acta 216:1?24
3. Durrant SF (1991) Brazilian Journal of Vacuum Applications 10:33?38
4. Jarvis KE (1989) J Anal At Spectrom 4:563?570
5. Balaram V, Manikyamba C, Ramesh SL, Saxena VK (1990) At Spectrosc 11:19?23