The following are a list of references that I've come across. I intend to keep this list up to date, replacing existing references with better when I find them. Please let me know if you know of any better (quality or comprehensiveness) or references that I have missed.

also, a list of my Favorite Software.

(Collected recently from PHP Meetup Group )

• Design Patterns Explained: a New Perspective on Object-Oriented Design by Alan Shalloway & James Trott (KCLS, paper only)
• PHP Object-Oriented Solutions by David Powers (KCLS, paper only)
• PHP 5 Objects, Patterns, and Practice by Matt Zandstra (KCLS, electronic only)
• UML Distilled : a Brief Guide to the Standard Object Modeling Language by Martin Fowler (KCLS, paper only)
• Patterns of Enterprise Application Architecture by Martin Fowler (SPL, paper only)
• Design Patterns: Elements of Reusable Object-Oriented Software by Gang-of-Four (KCLS, paper only, SPL, paper only)
• GRASP_(Object_Oriented_Design)
• Gang_of_Four_(software)

• Five common PHP design patterns
• Five *more* PHP design patterns ()

• BEST SITE: http://regexlib.com/
• http://www.regular-expressions.info
• http://www.wdvl.com/Authoring/JavaScript/JSChronicles/regexp.html
• http://www.visibone.com/regular-expressions/
• http://files.meetup.com/120908/Regexp%20Quick%20Reference.pdf

• Regular Expressions Tester Firefox Add-on