Advanced Raspberry Pi, Raspbian, Linux and GPIO Integration Second Edition by Warren Gay Raspberry Pi
Raspberry Pi 2 for Absolute Beginners, the Ultimate Guide to Get Started with Raspberry Pi 2 Master It Fast Raspberry Pi
Make Raspberry Pi and AVR Projects, Augment Your Pi with Analog ICs and the Chip That Powers Arduino by Cefn Hoile, Clare Bowman, Sjoerd Dirk Meijer, Brian Corteil and Lauren Orsini Raspberry Pi
Getting Started with Adafruit Trinket, 15 Projects with the Low Cost AVR ATtiny85 Board by Mike Barela Raspberry Pi