Conflict in Classification for Document Retrieval

States the conflict between changing the facet sequence and the Class Number of a subject to meet the needs of specialist readers on the one hand, and maintaining uniqueness of Class Number and of facet sequence as determined by postulates and principles on the other. Describes the method of bye-passing the conflict with the aid of Class Index Entries in generalist libraries, of formation of Favoured Collection in specialist libraries, and of inserting in the alphabetical index of a documentation list blocks of duplicates of relevant main entries under the name of the isolate of interest to the specialist reader.