1. A formula for predicting readability: Instructions;Edgar Dale;Educational Research Bulletin,1948
2. SMOG grading-a new readability formula;G Harry;Journal of reading,1969
3. Visual word recognition of three-letter words as derived from the recognition of the constituent letters;Don Bouwhuis;Perception & Psychophysics,1979
4. Lexical complexity and fixation times in reading: Effects of word frequency, verb complexity, and lexical ambiguity;Keith Rayner;Memory & Cognition,1986