Receive SMS with AT Commands using Sim900 and Arduino - The Engineering Projects
Amazon.com: Module,Development Board Module Kit,5~26V SIM Development Module,Fit for SIM900 850/900/1800/1900 MHz GPRS/GSM,Quad-Band 850/900/ 1800/1900 MHz - Would Work on GSM Networks : Electronics
GPRS Shield V2.0 | Seeed Studio Wiki
Basic AT Commands Testing in GSM Modem | GSM Module | Arduino - YouTube
SIM900/SIM900A GSM/GPRS Minimum System Module - ITEAD Wiki