Informetrics 87/88 : select proceedings of the First International Conference on Bibliometrics and Theoretical Aspects of Information Retrieval Diepenbeek, Belgium, 25-28 August, 1987 / ed. by Leo Egghe, Ronald RousseauInformetrics 89/90 : selection of papers submitted for the second International Conference on Bibliometrics, Scientometrics and Informetrics, London, Ontario, Canada, 5-7 July 1989 / ed. by Leo Egghe, Ronald RousseauIntroduction to informetrics : quantitative methods in library, documentation and information science / Leo Egghe, Ronald Rousseau