Papa, like many autodidacts I know who never made it to high-school, has read extensively, and you can find many references to world litterature, such as
Don Quichotte de la Mancha, a book he's very fond of,
or the Greek mythology,here it is the passage of the Styx, the river between life and death, with the "lovely" Charon in charge, described by Lucian (I think, though let me know if I'm wrong! But I remember studying a text in Greek class that my father read, and here is the result!). You can see also on that one, especially with Charon's head, Japanese influence.
Dad's always been very fond of the art of Japanese printmaking: Okusai in particular but many others and I'm sorry I do not have my Dad's culture and do not know many names!
The Greeks again or rather the people living in Crete, and a smidgen of Picasso I suppose.
For my book, of course, there won't be any images of hell, or fantastic landscapes, there will only be... well I don't know yet, but very probably a real landscape (si tant est que cela veuille dire quelque chose!) or clouds