ANSI X3J18
- Standard for "Programming Language REXX"
- http://www.rexxla.org/Standards/standards.html

IBM BookManager BookServer Library
- All IBM Rexx manuals and redbooks.
- http://publib.boulder.ibm.com/cgi-bin/bookmgr/FINDBOOK?filter=rexx

Six Rules of Thumb for Rexx
- This article gives six "rules of thumb" that should help get started in REXX if you already know C or Pascal (or, really, any of the children of Algol).
- http://www.uic.edu/depts/accc/software/regina/rexxrule.html

IBM Redbooks
- Search results for REXX.
- http://publib-b.boulder.ibm.com/cgi-bin/searchsite.cgi?query=rexx

SAA CPI REXX Level 2 Reference
- Old manual defining Rexx in the context of Systems Application Architecture.
- http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/E04A2A01/CCONTENTS

Kilowatt Software: Classic Rexx Tutorial
- Detailed language introduction.
- http://www.kilowattsoftware.com/tutorial/rexx/

CGI Scripts in REXX and Perl
- A guide by Les Cottrell.
- http://www-slac.slac.stanford.edu/slac/www/resource/how-to-use/cgi-rexx/

Rex Swain's REXX Summary
- Summary of REXX Functions, Syntax, Symbols, Operators, and Instructions
- http://www.rexswain.com/rexx.html

Jim Barry's Rexx Tutor
- Base on author training course at Computer Associates Training centre in Slough.
- http://www.kyla.co.uk/other/rexx1.htm