In textual criticism a version is a major revision of a work. In Latin, the verb vertere means to turn over, and in a very concrete sense, versions were used of texts which were changed e.g. from a metrical form to a prosaic form either within the same language or through the process of translation. Perhaps more frequently, the term is being used of any revision of a text which is so distinctive that each version may aspire to be regarded as a work of its own. However, as long as the revised form is referred to as a version, it is usually seen as belonging to a single work. In the FRBR typology, versions should be located to the level of expression, below the level of the work and above the level of manifestation (Functional Requirement for Bibliographical Records 1998, p. 14).
Versions are generally held to be of a higher level of difference than redactions and recensions of a work.
– Functional Requirements for Bibliographical Records. Final Report. München: Saur, 1998. – http://www.ifla.org/publications/functional-requirements-for-bibliographic-records. Accessed 1 November 2015.