1. Three-Membered Rings with Two Heteroatoms
2. E. Schmitz, in Comprehensive Heterocyclic Chemistry, ed. W. Lwowski, Pergamon Press, Oxford, 1984, vol. 1, p. 195.
3. H. W. Heine, in Small Ring Heterocycles, part 2, ed. A. Hassner, Wiley-Interscience, New York, 1983, ch. IV, pp. 547-629.
4. A new direction of ring expansion of 1,2-dialkyldiaziridines in the reactions with arylketenes