Ahmad ibn Muhammad from Al-Hasan ibn Ali ibn Faddal from Yunus ibn Ya'qub, who said:
I saw Abu Abdillah عليه السلام leveling the pebbles at the place of his prostration between the two prostrations.
Ali Akbar al-Ghaffari
Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 2, p. 326