The most prominent document about Collaboration over the World Wide Web is on http://www.w3.org/Collaboration/ .
From the site:
"Collaboration" over the World Wide Web is a very broad area of research, involving wide-reaching issues such as knowledge representation, annotation of objects by objects, notification, and any other issues which arise in the creation of shared information systems and collaborative development.
Test yourself if HalfFinishedWorkLeadsToCollaboration .