1. Computer-aided multivariate analysis;Afifi,1984
2. Skills for preschool teachers;Beatty,1984
3. Preschool appropriate practices;Beatty,1992
4. Have you ever thought of a prop box?;Bender;Young Children,1971
5. Interactive pretense: Social and symbolic skills in preschool play groups;Black;Merrill-Palmer Quarterly,1989