Coker, Alex; Hibbert, Frank (1995). "Substituent effects leading to ultra-slow proton removal from an intramolecular hydrogen bond". Journal of the Chemical Society, Perkin Transactions 2: 1. doi:10.1039/P29950000001.
"Back cover". Journal of the Chemical Society, Dalton Transactions (15): X059. 1994. doi:10.1039/DT99400BX059.