Data sources

• No need for a subscription key
• Usually provides cleaner and smaller number of irrelevant results than Google Scholar and Microsoft Academic
• Very good data source for “any of the words” key word searches and journal searches by ISSN
• Search speed fast to medium

• Typically reports fewer citations than Google Scholar and Microsoft Academic, because it includes fewer journals in some fields and has very limited coverage of books, book chapters and conference papers
• Author search is problematic as it is very difficult to disambiguate authors
• Year of publication is year of online-first, not year of print publication

• No need for a subscription key
• "Forgiving" search syntax
• Usually provides the largest number of publications and citations
• Search speed medium for single search with limited number of results

• Usually provides a larger number of irrelevant results than other data sources
• Author disambiguation more difficult than GSP, MA and WoS
• Because of necessary search rate limitation, speed slows down considerably when doing multiple searches in quick succession or running searches with many results
• Year of publication is sometimes - but not always - year of online first, not year of print publication

• No need for a subscription key
• Most "forgiving" search syntax
• Very quick search, 1-3 seconds for most authors
• Manual curation by the academic usually means cleaner results than GS

• Only available if academic in question has set up a profile
• Can contain "dirty data" if academic has not curated their profile
• Can be consciously manipulated by unscrupulous academics by adding papers not written by the academic themselves

• Usually provides a smaller number of irrelevant results than GS
• Search speed very fast for searches with less than 200 results, but fast even for repeated searches and searches with many results
• Usually provides cleaner results than GSP as not all user curate their GSP
• Seems to provide best automated author disambiguation

• More restrictive search syntax
• Does not allow NOT searches
• Year of publication is usually year of online first, not year of print publication
• Requires a (free) Microsoft subscription key

• Provides cleaner and smaller number of irrelevant results than Google Scholar and Microsoft Academic
• Typically reports more citations than Web of Science
• Very good data source for key word searches and journal searches by ISSN

• Requires a free API key from Elsevier for basic results
• Full results require (non-free) subscription
• Search speed slow, but still acceptable
• Typically reports fewer citations than Google Scholar and Microsoft Academic, because it includes fewer journals in some fields and has a limited coverage of books, book chapters and conference papers

Provides cleaner and smaller number of irrelevant results than Google Scholar and Microsoft Academic

Search speed very fast for nearly any kind of searches

Allows wildcards (e.g. global*) for easier searches

• Requires (non-free) subscription
• Typically reports fewer citations than all other sources because it includes fewer journals in many fields (esp. Social Sciences and Humanities) and has a very limited coverage of books, book chapters and conference papers.
• Typically is last data source to include recent publications as it doesn’t include “in press” papers.