OPITZ HELMUT 803,402 WORLD World guide to special libraries / [eds: Bettina Bartz, Ruth Lochar, Helmut Opitz]. - 2 ed. - München. K.G. Saur, 1990. - 2 vol. ; 31 cm Vol. 1. , Libraries A-L. - XXXIV, 606, [1] s. Vol. 2. , Libraries H-Z Index. - [7], 609-1196 s. (Handbook of International Docunentation and Information : vol. 17) ISBN 3-598-22230-0