1. Kienitz, H, Runge, H. in Korte, F. (ed.): Methodicum Chimicum, vol. Ia, p. 839 (1973), Thieme Verlag, Stuttgart, ISBN 3-13-480101-9
2. Steyn, J.M., Müller, F.O.: S. Afr. Med. J. 57, p. 129 (1980)
3. Verbiese-Genard, N., Hanocq, M. et al.: Analyt. Biochem. 134, p. 170 (1983)
4. Scales, B. in Reid, E. (ed.): Blood, Drugs and Other Analytical Challenges, pp. 43–54 (1978), Ellis Horwood Ltd., Chichester (Sussex), ISBN 0-85312-124-9
5. Adam, H.K., in Reid, E. (ed.): Trace-Organic Sample Handling, pp. 291–297 (1980), Ellis Horwood Ltd., Chichester (Sussex), ISBN 0-85312-187-7