1. Roumanian Patent No. 110034 (23. 10. 1995), C. C. Ponta.
2. E. A. Evans, Tritium and its Compounds, Pergamon Press, London, 1980.
3. A. T. Balaban, I. Galateanu, Gh. Georgescu, L. Simionescu, Labeled Compounds and Radiopharmaceuticals Applied in Nuclear Medicine, Acad. Bucuresti-Romania and John Wiley & Sons Ltd., 1986.
4. C. I. Postolache, C. C. Ponta, C. Postolache, I. Mihalcea, I. Georgescu, Roum. Biotech. Lett, 2 (1997) 321.
5. W. J. Gensler, W. R. Kochler, J. Org. Chem., 27 (1962) 2754.