[TUHS] where to download 4.1BSD, 4.1a, 4.1b, 4.1c and others?

[Jeremy C. Reed]

I see The Unix Tree has browsable "4.1c BSD". Where can I download this 
(so I don't have to browse)?

Also where can I find downloads for 4.1BSD and 4.1aBSD and 4.1cBSD and 
anything after 2BSD but before 2.79BSD?

Thanks

Jeremy C. Reed