Rogers: A Brief Introduction to Distributed Cognition
Distributed Cognition is a hybrid approach to studying all aspects of cognition, from a cognitive, social and organisational perspective. The most well known level of analysis is to account for complex socially distributed cognitive activities, of which a diversity of technological artefacts and other tools and representations are an indispensable part.
http://mcs.open.ac.uk/yr258/papers/dcog/dcog-brief-intro.pdf