1. SparkFun Electronics, 6175 Longbow Drive, Suite 200, Boulder, CO 80301 (www.sparkfun.com)
2. Arduino homepage (www.arduino.cc)
3. Atmel 8-bit AVR Microcontroller with 4/8/16/32K Bytes In-System Programmable Flash, AT- mega48PA, 88PA, 168PA, 328P data sheet: 8171D-AVR-05/11, Atmel Corporation, 2325 Orchard Parkway, San Jose, CA 95131.