Synthesis Grafted on to an Enumerative Scheme

There are two major examples of synthesis being grafted on to an enumerative scheme. The first dates back to the turn of the century when the Universal Decimal Classification was formulated. This scheme, which has been issued in a number of different languages and has progressed through a number of editions, was based upon the Dewey Decimal Classification but signs of combination and abbreviation were introduced to allow for number building. The second scheme is of much more recent origin and is the ongoing revision of the Bibliographic Classification.