Amazon.com: Texas Instruments NE555P IC Single Precision Timer (Pack of 12) : Industrial & Scientific
555 Timer IC - Working Principle, Block Diagram, Circuit Schematics
Amazon.com: The Ultimate Beginner's Guide to the 555 Timer: Build the Atari Punk Console and Other Breadboard Electronics Projects eBook : Rutherford, Jesse: Kindle Store
555 timer teardown: inside the world's most popular IC