Robert E. Erard & Irene Fast 
Event Theory [PDF ebook] 
A Piaget-freud Integration

First published in 1985. The event model presented in this study, attempts a framework for integrating psychoanalytic and Piagetian psychologies centered in the notion that development occurs by the differentiation of self and nonself. Its aim is to understand phenomena conceptualized in psychoanalytic terms in a model based on this Piagetian perspective, or, in other words, to provide an object-relational model for the development of psychic structure analytic and Piagetian psychologies centered in the notion that development occurs by the differentiation of self and nonself.