NON CONVENTIONAL INDEXING MODEL - CITATION INDEXING
Another unique indexing model was developed by Eugene Garfield in early 1960's. The model is non conventional in the sense that it does not use subject terms in indexing. Instead, the indexing is done by the name of author - cited and citing references to sources. Here, the name of the author, the source document where a particular paper is published is taken into consideration. The author and the source document cited are considered for indexing. This indexing named as Citation Indexing and developed on the same idea of Shepherd's Citation index is a unique example of a non conventional model. Here, the problems of citation order, semantics, change of terminologies of a subject are automatically solved, as it is not based on terminologies. Studies have shown that it works quite well in providing subject approach to information. The Science Citation Index, Social Science Citation Index and Arts and Humanities Citation Index are the examples of this model.