Introduction to Unix Command Line - IBM developerWorks, 2006-2007 (four part series)
Screen command for CLI multi-session persistence - IBM developerWorks, Feb 2009
Understanding Unix processes - IBM developerWorks, April 2007
Cygwin - Unix environment for Windows - IBM developerWorks, Dec 2008
Speaking Unix - IBM developerWorks series
Quick introduction to Unix files and processes - WIkiBooks, May 2012
Linux Professional Institute exam prep - IBM developerWorks, 2005-2009
Unix Basics - Swiss Bioinformatics Institute, 2009