A broad range of weblinks for every chapter to further your reading and act as sources.

The website of the Jean Piaget Society which is a good source of further information about Piaget’s life and work:
http://piaget.org/

A talk by Renee Baillargeon about her research on infants’ knowledge of the physical world, including their understanding of object permanence:
https://www.youtube.com/watch?v=Zd7OIDm_btM