most of the core libraries which ensure that PSPP runs with optimal
speed are his work.
-* John Darrington wrote the graphical user interface, and the T-TEST,
-ONEWAY, EXAMINE, RANK and NPAR TESTS commands, implemented support for
+* John Darrington wrote the initial version of the graphical user interface,
+and many of the statistical procedures. John also implemented support for
long variable names, PostgreSQL and Gnumeric and made numerous
revisions to other modules.
* Mehmet Hakan Satman wrote the QUICK CLUSTER command.
+* Friedrich Beckmann wrote the GRAPH command.
+
We also thank past contributors:
* John Williams wrote an initial draft of the T-TEST procedure.