Rao, K. V. B.; Charles, E. S.; Sharma, Satyavan, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1981, vol. 20, # 7, p. 575 - 578
Rao, K. V. B.; Charles, E. S.; Sharma, Satyavan, Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1981, vol. 20, # 7, p. 575 - 578