Biswas, K. M.; Dhara, R. N.
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1982 , vol. 21, # 7 p. 632 - 637

Biswas, M. Kshetra; Dhara, Rabindranath; Roy, Sumita; Mallik, Haimanti
Tetrahedron, 1984 , vol. 40, # 21 p. 4351 - 4357