From the first link below ...

"The Distributed Cognition (dcog) approach was developed by Ed Hutchins and his colleagues at University California, San Diego in the mid to late 80s as a radically new paradigm for rethinking all domains of cognitive phenomena. The traditional view of cognition is that it is a localised phenomenon that is best explained in terms of information processing at the level of the individual. In contrast Hutchins was making the claim that cognition is better understood as a distributed phenomenon" (Yvonner 1) 


Some links:

A Brief Introduction to Distributed Cognition
http://www.cogs.susx.ac.uk/users/yvonner/papers/dcog/dcog-brief-intro.pdf

An ethnographic study of groupware systems in use
http://www.ai.univ-paris8.fr/corpus/papers/brown/toc.htm

Shared Understanding: Implications for Computer Supported Cooperative Work
http://www.dgp.utoronto.ca/people/WilliamHunt/qualifier.html

Technical implications of distributed cognition on the design on interactive learning environments.
http://tecfa.unige.ch/tecfa/publicat/dil-papers-2/Dil.7.2.9.pdf
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