Ellis, David
Progress and problems in information retrieval
Library Association Publishing, 1996
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Hill, Norman
International organization
Harper & Brothers, 1952
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Progress in approximation theory: an international perspective
edited by A.A. Gonchar and E.B. Staff
Springer-Verlag, 1992
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Progress in language planning: international perspectives
edited by Juan Cobarrubias and Joshua A. Fishman
Mouton, 1983
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Problems and progress in medical care: essays on current research
edited by Gordon Mclachlan
Oxford University Press, 1970
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