Google Scholar, Web of Science, and Scopus: A systematic comparison of citations in 252 subject categories - Martín-Martín, Alberto; Orduna-Malea, Enrique; Thelwall, Mike; Delgado López-Cózar, Emilio (Journal of informetrics, 2018)
Keywords: Academic search engines; Bibliographic databases; Bibliometrics; Citation analysis; Citation overlap; Coverage; Google Scholar; Scientometrics; Scopus; Unique citations; Web of Science; Web of Science; Unique citations; Scientometrics; Citation analysis; Bibliometrics; Scopus; Citation overlap; Bibliographic databases; Coverage; Academic search engines; Google Scholar