Making a digital library: the chemistry online retrieval experiment
The CORE project is an electronic library of primary journal articles in chemistry, containing about five years of twenty primary journals published by the American Chemical Society (about 425,000 pages). Unlike many digital library projects, CORE includes both a scanned image and a marked-up ASCII version (represented in Standard Generalized Markup Language, or SGML) for each page of the publisher's database. Each page was scanned and segmented, with graphical units isolated and linked to figure references in the articles. The original machine-readable typography was converted to SGML format and the results were used to build databases with indexes for full-text Boolean searching; a single search engine served data for each of three X-Window interfaces.