Tweet Columbia Pictures - Archival Sources?

This is for anyone who has done research into Columbia, particularly the mid 1930s. Are there any good archival sources in public collections - studio memos and the like? Anecdotally, I understand that sources for Columbia are less plentiful than for the other major studios, but Bernard F. Dick's "The Merchant Prince of Poverty Row" makes reference to studio teletypes, so there must be some available. Does anybody have any leads?

Arne Andersin's "Lost Film Files" website lists the company's lost films from the years 1925 to 1929. That's about all I know. A book called The Columbia Story may have been put out in the 80s, along with like books on Paramount, Universal, UA etc...don't know if that's what you're looking for.

That's a start ... my specific interest is the development of Columbia's co-production policy in the mid 1930s. It's one of the reasons 'The Columbia Story' is a little hazy about what films should and shouldn't be included in the studio's official canon (it includes an appendix of the co-productions; even this is not complete). Some were wholly funded by the studio but made overseas, some were made by independent producers working at Columbia Studios, and so on. No two were alike, and as far as I know, it was quite an unusual practice at the time.

What I'm particularly interested in is that there were some internal disputes within Columbia over some of the international productions that were made in Australia, in which Harry Cohn became personally involved. I'd be really interested in some sort of primary source - studio memos and the like - that might give some further details.