One specific article within a general encyclopedia, cited as the source for a particular fact about a particular topic, theory or person, rather than the encyclopedia's own general presence. Belongs here: individual Wikipedia articles such as Wikipedia: Cooperative learning, Wikipedia: Dual-coding theory and Wikipedia: George Siemens, each cited for one topic's facts. Does not belong here: the encyclopedia's own home page or general presence cited as a source in its own right, filed under General Encyclopedia, and a specialist academic reference article, filed under Academic Philosophy Reference rather than here.