Musnad Abu Ya'la al-Mawsili 6:111

Zuhayr narrated to us, Abd al-Rahman ibn Mahdi narrated to us, Wuhayb narrated to us, from Abu Waqid al-Laythi, from Amir ibn Sa’d, from his father, that the Prophet (peace and blessings of Allah be upon him) said: "The hand is cut off for the price of a shield."