Hadith 822
أن النبى صلى الله عليه وسلم أذن فى أذن الحسن بن على يوم ولد فأذن فى أذن اليمنى وأقام فى أذنه اليسرى
"On the day Hasan bin Ali (may Allah be pleased with them both) was born, the Noble Prophet (peace and blessings be upon him) recited the adhan in his right ear and the iqamah in his left ear."