Hansen, John F.; Kim, Yong In; Griswold, Linus J.; Hoelle, Gary W.; Taylor, Deborah L.; Vietti, David E.
Journal of Organic Chemistry, 1980 , vol. 45, # 1 p. 76 - 80
Hansen, John F.; Easter, John A.; Eckert, David A.; Hunt, Karen J.; Little, David A.
Journal of Heterocyclic Chemistry, 1994 , vol. 31, # 2 p. 281 - 286