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In practice, citations are counted from the citation databases, and citations to publications that are not included in the databases are not counted. Thus, more than the length of the reference lists, the extent to which the field publishes in series and books indexed by the citation databases, and the proportion of citations to these, has a more significant impact on the typical number of citations in the field of research (Dorta-González & Dorta-Gonzáles, 2013; Patience et al., 2017).
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