Intertextuality has been a much used term since its first introduction by Julia Kristeva in her work of the late-1960s, notably her essay of 1969, translated as “Word, Dialogue and Novel” (reprinted in Toril Moi, ed. The Kristeva Reader), on Bakhtin’s Rabelais and his World, his theory of carnival and other aspects of his dialogic account of language and literature. The fundamental concept of intertextuality is that no text, much as it might like to appear so, is original and unique-in-itself; rather it is a tissue of inevitable, and to an extent unwitting, references to and quotations from other texts. These in turn condition its meaning; the text is an intervention in a cultural system. Intertextuality …
Allen, Graham. "Intertextuality". The Literary Encyclopedia. First published 24 January 2005; last revised 30 November -1.
[http://www.litencyc.com/php/stopics.php?rec=true&UID=1229, accessed 28 April 2015.]