Hi, a study has been done by the Boise Library, USA The Journal Stop: A Complete Serials Information System : http://lester.boisestate.edu/tdnet/journalstop.htm Hope it will help you Emmanuel Collier Médiathécaire Pôle Science et Société Cité des Sciences et de l'Industrie Avenue Corentin Carriou, Paris http://www.cite-sciences.fr