View source for MUMPS/MUMPS-15/20200522

from https://www.mail-archive.com/simh@trailing-edge.com/msg08975.html
<pre>
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

</pre>