VMS on Mach: http://dl.acm.org/citation.cfm?id=964616 - There's a PS version of this floating around, too.
MS-DOS on Mach: https://www.cs.cmu.edu/afs/cs/project/mach/public/www/doc/ab...
I'm never sure whether NeXTStep counted as BSD running on top of Mach, or if NeXT built it in to Mach.