Intertextuality is the juxtaposition of two texts which together create a new meaning that is not contained in either text when used alone. The term was introduced by semiotician Julia Kristeva in the late 1960's. It has much potential for use in artists books and I think it could and should be a method used by artist book makers more often.
I first used intertextuality as a means of creating meaning in an artwork I made in 1993.
The piece was a sculptural book made of calfskin vellum called In the Beginning Far off in the Dreamtime. The form of the book is an icosahedron - a crystal shape created in nature. This icosahedron carries excerpts from two different creation texts, In the beginning from Genesis in the bible and Far off in the Dreamtime, the story of the Rainbow Serpent. By juxtaposing the texts, meaning and issues not contained in the individual texts were created, relating to Australian/Aboriginal cultural issues, reconciliation and belief systems.
A recent print of his called Shelf Isolation 2020 utilises these book titles to create a new story about the pandemic.
Phil Shaw has made a number of different Bookshelves in this series and you can read how he creates the prints and view others in the series on his website here or at the Rececca Hossack Art Gallery in London here.