The below is taken directly from the SPSS website here.
For most of our products, you can get the complete product name, version or release number and date of creation from the "About . . ." dialog box that appears under the "Help" menu. For example, if you have SPSS for Windows, you might see this:
SPSS for Windows Release 11.0.1 (15 Nov 2001) You can then write a bibliographic citation as follows:
SPSS for Windows, Rel. 11.0.1. 2001. Chicago: SPSS Inc.
If you are referencing material from the SPSS Web site, please refer to the terms and conditions here.
typing
citation()
at an R prompt will give the citation for referencing R procedures: e.g. in R 2.14.2 we get
R Development Core Team (2012). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0, URL http://www.R-project.org/.