Shares of the categories (research fields) to which the journals (according to the Journal Citation Reports [InCites, 2017]) belong that contain the articles cited in a WUR article with a low dissimilarity (left) and a WUR article with a high dissimilarity (right). Both WUR articles have been published in the journal Ecology and respectively cite 31 and 35 articles in journals for which category information can be obtained from the Journal Citation Reports (InCites, 2017)