Of the three approaches, author approach is most common. There are several reasons for it. The first of these is that the author's name is an easily identifiable element, as it is very clearly stated on the title page of a book. Another reason is that an author is "the person chiefly responsible for the creation of the intellectual or artistic content of a work" (AACR-2). This gives rise to the concept of intellectual responsibility coming down to use from the historical tradition of scholarship. Initially, libraries and their catalogues were developed for the scholar for whom it was necessary to bring all works of an author at one place and an author catalogue served this purpose very well. The importance of an author at one place and an author catalogue is so much that all codes of cataloguing from 1908 Anglo-American Code to AACR-2 embody mainly rules for author entries. However, as early as 1876, Charles Ammie Cutter showed keen interest in subject cataloguing and developed his remarkable Rules for a Dictionary Catalogue. With the development of science libraries, subject catalogue has been growing in importance. Author catalogue, nevertheless, remains predominant irrespective of the type of library. No wonder then that all printed catalogues of the major libraries of the world are author catalogues, e.g., British Museum General Catalogue of Printed Books.