Intertextuality is defined here. It is a way to enrich a text by using reference to another text.
What would be a good reference on this subject?
There are always other words in a word, other texts in a text. The concept of intertex- tuality requires, therefore, that we understand texts not as self-contained systems but as differential and historical, as traces and tracings of otherness, since they are shaped by the repetition and transformation of other textual structures. Rejecting the New Critical principle of textual autonomy, the theory of intertextuality insists that a text cannot exist as a self-sufficient whole, and so, that it does not function as a closed system. (María Jesús Martínez Alfaro, 'Intertextuality : Origins and Development of the Concept', Atlantis, Vol. 18, No. 1/2 (Junio - Diciembre 1996), pp. 268-285 : 268.)
This agrees with your reference; I include it to get a concise statement of the concept on screen.
There's a wealth to choose from :
Clayton, Jay and Eric Rothstein, eds. 1991. Influence and Intertextuality in Literary History. Madison: University of Wisconsin.
Culler, Jonathan 1976. Presupposition and Intertextuality. Modern Language Notes 91: 1380-396.
Foucault, Michel 1972 (1971). The Discourse on Language. The Archeology of Knowledge and the Discourse on Language. Trans. A. M. Sheridan Smith. New York: Harper & Row. 215-37.
Friedman, Susan Stanford 1991.'Weavings: Intertextuality and the (Re)Birth of the Author', Influence and Intertextuality in Literary History . Eds. Jay Clayton and Eric Rothstein. 146-80.
Johnson, Barbara 1987. 'Les Fleurs du Malarme: Some Reflections on Intertextuality', A World of Difference. Baltimore: Johns Hoppkins U.P, 116-133.
Plett, Heinrich F. 1991. Intertextualities. Intertextuality. Ed. Heinrich F. Plett. Berlin: De Gruyter. 3-29.
Worton, Michael and Judith Still, eds. 1990. Intertextuality: Theories and Practices. Manchester: Manchester University Press.