RDS3231 Class is by Seeed Technology Inc(http://www.seeedstudio.com) and used in Seeeduino Stalker v2.1 for battery management(MCU power saving mode) & to generate timestamp for data logging. DateTime Class is a modified version supporting day-of-week. Original DateTime Class and its utility code is by Jean-Claude Wippler at JeeLabs http://jeelabs.net/projects/cafe/wiki/RTClib Released under MIT License http://opensource.org/licenses/mit-license.php