Musnad Ahmad 430:22

'Abd al-Razzaq narrated to us, he said: Ma'mar informed us, from Ayyub, from Sa'id ibn Jubayr, he said: I was with 'Abdullah ibn Mughaffal, and a man from his people flicked a pebble [with his fingers] in his presence. Then he mentioned the hadith. Abu 'Abd al-Rahman [Ahmad ibn Hanbal] said: "Ma'mar erred in this, because Sa'id ibn Jubayr did not meet 'Abdullah ibn Mughaffal."