Al-Kāfi

9. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from al-Husayn ibn Sa‘id from Fadalah ibn Ayyub from Al- Husayn ibn ‘Uthman from ibn Muskan from ‘Anbasah ibn Mus’ab who has said the following: “I once asked abu ‘Abd Allah (a.s.), about a man who performs Salah (prayer) behind an Imam and there is no one on his left side; how he says the phrase of offering greeting of peace?’ He (the Imam) said, ‘He says the phrase of offering greeting of peace only once to his right side.’”