1. Structure and Mechanism in Organic Chemistry, Cornell University Press, Ithaca, New York, 1953 , chapter 46e.
2. O. Häfliger in Determination of Organic Structures by Physical Methods (Eds.: Academic Press, New York, 1955 , pp. 567-662.
3. M. Charton in Similarity Models in Organic Chemistry, Biochemistry and Related Fields (Eds.: Elsevier, Amsterdam, 1991 , pp. 629-687.