Selvaraj, S.; Rajendran, A. S.; Arumugam, N.
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1987 , vol. 26, # 1-12 p. 1047 - 1049

Rodionow; Fedorowa
Chemische Berichte, 1927 , vol. 60, p. 805