Import GFX into a grease penciel layer?

Hi there, i was worndering if there is a way to import graphics as illustrator curve (example) or such into or rather onto a grease penciel layer. So in general I would like to have a workflow, in which the graphics start as traditional drawing on paper, get scanned and turned into a vector based image format and then get placed onto the grease penciel layer. Is that possible? Somebody knows a way how to do it?
Best regards
Heiner