It has been over twenty years Since Clymer published his pioneer phonic generalization study. In this study Clymer selected four widely used basal reader manuals from which he culled over 150 consonant and other word attack generalizations, including some that had been used without question from the time that phonic generalizations were first introduced by Noah Webster.
Gates, L. (1986). The Consonant Generalizations Revisited. Reading Horizons, 26 (4). Retrieved from https://scholarworks.wmich.edu/reading_horizons/vol26/iss4/2