Shafiee, A.; Vossoghi, M.; Savabi, F.; Vlahov, R.; Tarpanov, V.; et al.
Steroids, 1983 , vol. 41, # 3 p. 291 - 308

Arnarp, Jan; Enzell, Curt; Petersson, Kurt; Pettersson, Tore
Acta Chemica Scandinavica, Series B: Organic Chemistry and Biochemistry, 1986 , vol. 40, # 10 p. 839 - 854