1. and in and (Eds.), Advances in Heterocyclic Chemistry, Vol. 10, Academic Press. New York, 1969, p. 241.
2. and J. Chem. Soc. 1646 (1964).
3. Über den Austausch von Pyridin‐Stickstoff gegen Oxonium‐Sauerstoff (III. Mitteil. über Oxonium‐Salze
4. and in (Ed.), Computer Programs for Chemistry, Vol. 1, W. A. Benjamin, New York, 1968, p. 10.