- * Jim Van Zandt translated the `julcal' date calculation package
- into C from code written by Michael Covington, which was based on
- formulae by Jean Meeus.
+* John Darrington wrote the graphical user interface, and the T-TEST,
+ONEWAY, EXAMINE, RANK and NPAR TESTS commands, implemented support
+for long variable names, psql and gnumeric and made numerous revisions
+to other modules.
+
+* Jason Stover contributed statistical and numerical functionality,
+including lib/gslextras and the linear regression features. Jason
+is also an important contributor to GSL, which is used by PSPP.
+
+
+We also thank past contributors:
+
+* John Williams wrote an initial draft of the T-TEST procedure.
+
+* Michael Kiefte contributed bug fixes and other enhancements.
+
+* Patrick Kobly contributed bug fixes and other enhancements.
+
+* Rob van Son wrote the original version of the routine for
+ calculation of the significance of the Wilcoxon matched pairs signed
+ rank statistic used by the NPAR TEST command.