MUMPS/MUMPS-15/20200522
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Bob Supnik Fri, 22 May 2020 09:38:36 -0700 Before MUMPS-11, there was MUMPS-15. It is the only one of the PDP-15's DEC operating systems that is still missing. TA PDF assembly listing of XVM/MUMPS-15 (or perhaps only part of it) exists, but it is scribbled over in places, as though it were a developer's "in progress" listing. There's also a pocket card for a PDP-9 timesharing system developed at the Ontario Institute for Studies in Education. No other trace has been found. /Bob