What is co-citation?

Co-citation is when two papers are both cited by a third paper. The more often two papers are cited together, the more the research community treats them as related. Co-citation analysis maps the intellectual structure of a field, and is the idea behind many “related papers” tools.

Co-citation favours older, well-cited papers, since it needs citing papers to accumulate.

Its mirror, bibliographic coupling, relates papers that cite the same sources.