THE REFERENCE SOURCES/ BOOKS:

A basic question arises then when we start discussing reference books, that is what books and other materials a reference library should stock and how they should be organised so as to constitute a reference collection. The reference collection should include three classes of materials: 

•  reference books such as, Dictionaries, Encyclopaedias, Bibliographies, Yearbooks, Directories, Biographies; 

•  standard works of information such as Gazetteers, Atlases, etc.; 

•  all such materials that cannot be lent for home reading such as indexing and abstracting periodical, statistical sources; and 

In the above, the first two categories are intended to fulfill the genuine function of a reference library that is - the supply of information. 

Reference books are referred to as compilation, specifically designed to provide items of in-formation in a most convenient form. The main conventional categories are encyclopaedias, dictionaries, directories, yearbooks,  bibliographies biographical and geographical information sources. The reference collection of any library should include the best and latest editions of the encyclopaedias, dictionaries and other reference books, bibliographical sources, indexes, catalogues and guides, standard histories and gazetteers,  editions of the  classic works of literature. Authoritative works on other subjects  should be added as  far as budget permits, especially those, which are more fitted for occasional consultation rather than for continuous reading. 

The reference books are many in number. No single library can afford to buy all the available reference sources. Also there is no available required list, which may indicate ideal reference collection for an ideal library. More complexity has arisen due to availability of reference  books in other  media other than the print media. But ultimately, the best reference collection is said to be the one, which is useful for both the reference librarian and the users. For convenience sake, peers have  classified the reference sources into primary sources, secondary sources and tertiary sources based on the type of information sources included in them.