* Ben Pfaff wrote most of the program and the manual.

* John Darrington wrote the graphical user interface, and the 
T-TEST, ONEWAY, EXAMINE, RANK and  NPAR TESTS commands, implemented
support for long variable names and made numerous revisions to other 
modules.

* Jason Stover contributed statistical and numerical
functionality, including lib/gslextras.  (Jason is also an
important contributor to libgsl used by PSPP.)