In the context of contemporary art, the term "multiple" refers to an object that is composed of a certain number of serial, manufactured objects that are economically, physically and aesthetically equal or similar. This entity reflects both the existence and the absence of the objects of its series and will be authorized in a final step by the author. Furthermore, the multiple does not maintain itself by any vertical reference to something more significant or original but by a horizontal reference to something equal and concurrent. (Pias 2006, paraphrase and translation by the author)