حَدَّثَنَا عَلِيُّ بْنُ مُحَمَّدٍ، حَدَّثَنَا وَكِيعٌ، حَدَّثَنَا الأَعْمَشُ، عَنْ عُمَارَةَ بْنِ عُمَيْرٍ، عَنْ أَبِي مَعْمَرٍ، قَالَ قُلْتُ لِخَبَّابٍ بِأَىِّ شَىْءٍ كُنْتُمْ تَعْرِفُونَ قِرَاءَةَ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ فِي الظُّهْرِ وَالْعَصْرِ قَالَ بِاضْطِرَابِ لِحْيَتِهِ ‏.‏

It wasnarrated that Abu Ma’mar said: “I said to Khabbab: ‘How didyourecognize that the Messenger of Allah (PBUH) was reciting in theZuhrand the ‘Asr?’ He said: ‘From the movement of his beard.’” Translation Not Available

Book Ref: Sunan Ibn Majah Book 5 Hadith 826
Web Ref:  Sunan Ibn Majah Vol 1 Book 5 Hadith 826

---