Swaminathan et al.
Journal of Organic Chemistry, 1958 , vol. 23, p. 707,709

Mahboobi; Grothus; Meindl
Archiv der Pharmazie, 1994 , vol. 327, # 2 p. 105 - 114

Hiremath, Shivayogi P.; Thakar, Shreeram B.; Purohit, Muralidhar G.
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1984 , vol. 23, # 10 p. 926 - 929