Good luck with this project, which will undoubedly yield interesting results.

I think it's obvious that all of us, always, are "influenced" by everything we hear, and that the synthesis of European and African musical expression that resulted in American music has always been a two-way street. However, "proving" this contention in a scholarly manner can be problematic. The actual hearing and playing and feeling of music does not necessarily ever get written down and preserved as a "source" that one can footnote.

There is certainly a lot of documentation concerning the early Creole jazz players in New Orleans, specifically about their European-style formal musical education. The first jazz ensenmbles were Creole orchestras already adept and reading sheet music, playing operatic and "light-classical" music as well as popular material.

There are plenty of books on this topic, including works by Jason Berry, Jeff Hannusch, Al Rose, Ben Sandmel, and plenty of others. I can't promise, but maybe I'll be back with a few specific references.

Also ~ this is probably too recent a musical development to include, when I first saw the title "White Influence on Black Music," the first thing I thought of was Ray Charles landmark recording "Modern Sounds in Country and Western Music."