A. C.  Garade, Kshirsagar, V. S., and Rode, C. V., ?Selective hydroxyalkylation of phenol to bisphenol F over dodecatungstophosphoric acid (DTP) impregnated on fumed silica?, Applied Catalysis A-General, vol. 354, no. 1-2, pp. 176-182, 2009.