Lampman, Gary M.; Koops, Roger W.; Olden, Caroline C. (1985). "Phosphorus and sulfur ylide formation: Preparation of 1-benzoyl-2-phenylcyclopropane and 1,4-diphenyl-1,3-butadiene by phase transfer catalysis". J. Chem. Ed.62 (3): 267. doi:10.1021/ed062p267.