IRS13 Scientific Report No. IRS-13 Information Storage and Retrieval Test Environment chapter E. M. Keen Harvard University Gerard Salton Use, reproduction, or publication, in whole or in part, is permitted for any purpose of the United States Government. 1-6 TIME CRAN-2 ISPEA/EURATOM MEDLARS CHARACTERISTICS MAGAZINE Aerodynamics Section on Subject area and[OCRerr]Aircraft Documentation Medicine world news Structures Number of[OCRerr] documents if 400 1,268 276 c600 Abstracts Document length and indexing Abstracts Abstracts Full text Number of requests 225 48 18 c50 Characteristics of Four New Test Environments Fig. 2