Including cited non-source items in a large-scale map of science: What difference does it make?
作者：
Highlights：
• A direct citation map containing a combination of 43 million source and non-source documents has been created.
• Over half of the documents in the map are non-source documents.
• The social sciences are much more heavily represented by non-source items, and assume a more central position in the map.
• Over 500,000 books appear in the map; these are much more highly cited on average than articles.
摘要
•A direct citation map containing a combination of 43 million source and non-source documents has been created.•Over half of the documents in the map are non-source documents.•The social sciences are much more heavily represented by non-source items, and assume a more central position in the map.•Over 500,000 books appear in the map; these are much more highly cited on average than articles.
论文关键词：Science mapping,Direct citation,Non-source documents,Books
论文评审过程：Received 3 February 2014, Revised 28 March 2014, Accepted 2 April 2014, Available online 17 May 2014.
论文官网地址：https://doi.org/10.1016/j.joi.2014.04.001
