1. Beginning to read: Thinking and learning about print;Adams,1990
2. Letters, sounds, and symbols: Changes in children's understanding of written language;Bialystok;Applied Psycholinguistics,1991
3. Children make sense of numbers: The development of ideas about written numerals;Brenner,1989
4. The underlying logic of literacy development;Ferreiro,1984
5. L'ecriture avant la lettre;Ferreiro,1988