Citation is the citation of another author's work in one's publication. Self-citation occurs when there is at least one common author for the citing and cited publication. Reduced data, i.e. data that do not include self-citation, are taken into account in the citation analysis.

The number of citations is calculated both for a single article and the output of the scientist, as well as the output of the entire scientific unit. Thus, citation analysis is a study of the impact and, by implication, quality of a publication, author, institution based on how many times this work and/or author has been cited by others.

A source of information useful in preparing a citation analysis is bibliometric databases: databases that index citations.