8. Jonas PMM, Eve DJ, Parrish JR, Talanta, 36, 1021 (1989)
9. Furniss BS, Hannaford AJ, Smith PWG, Tatchell ARVogel's Text Book of Practical Organic Chemistry, 5th ed., Longman Scientific and Technical co published with John Wiley and Sons Inc., New York, 1034 (1991)