title: Citation indexing for studying science.
mesh_terms: D000043:Abstracting and Indexing; D005823:Genetics / Q000266:history; D049672:History, 19th Century; D049673:History, 20th Century; D007256:Information Systems; D009613:Nobel Prize; D010414:Pennsylvania; D012106:Research; D012586:Science / Q000266:history; D012963:Sociometric Techniques