Piaget for Teachers
Hans G. Furth
Knowledge Representation and Organization in Machine Learning
Katharina Morik
Selecta Mathematica - Volume 1
Karl Menger
Longman Photo Dictionary
Pearson Education, Limited
Play, Dreams and Imitation in Childhood
Jean Piaget
Das Geheimnis der Geheimnisse (Übersetzt)
Uell S. Andersen