1. An apparatus comprising: at least one processor; and a memory coupled to said at least one processor storing: a markup language document containing: a markup language element hierarchy containing a set of markup language elements; and a plurality of references to said markup language element hierarchy; and machine-executable code which, when executed by the at least one processor, generates, from said markup language document, another markup language document containing one instance of said set of markup language elements for each of said plurality of references.