different between intertextuality vs intratextuality

English

From French intertextualité.

intertextuality (plural intertextualities)

The idea that a given text is a response to what has already been written, be it explicit or implicit.
The reference to another separate and distinct text within a text.

intratextuality (countable and uncountable, plural intratextualities)

The quality of being intratextual.
A reference by a text to itself.
- 2010, Joseph Farrell, Michael C. J. Putnam, A Companion to Vergil's Aeneid and its Tradition (page 183)
  Spenser has an intimate feel for Vergilian intratextuality, the mirrorings and repetitions that create patterns of likeness and difference, reaching over the whole text and linking images, motifs, and persons.

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