During our discussions of ekphrasis, Maria asked an intriguing question: What's the difference between intertextuality and allusion? There's no one answer to this question, and depending on who you ask, you'll get a different answer. But this doesn't mean that there haven't been worthwhile explorations of intertextuality, allusion, and distinctions between the two.
Here are some resources:
Julia Kristeva's Desire in Language (JK credited with coining "intertextuality")
This webpage is okay for various ways in which the two terms have been defined, as well as for providing examples in visual texts
William Irwin, "What is an Allusion?"
William Irwin, "Against Intertextuality"
A good introduction to intertextuality (and example) on YouTube here
