Quellenforschung
/ˈkvɛlənˌfɔːʃʊŋ/noun
The study of the sources of, or influences upon, a literary work.
Origin
Late 19th century; earliest use found in American Journal of Philology. From German Quellenforschung from Quellen-, combining form of Quelle source + Forschung investigation, research (Old High German forscunga, Middle High German vorschunge) from forschen to search (for), to conduct research + -ung.