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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
ahmad:12750 – Muḥammad b. Jaʿfar > Shuʿbah > Hishām b. Zayd > Anas b. Mālik

So far as I know (he was cauterising) their ears. (Using translation from Muslim 2119b)  

أحمد:١٢٧٥٠ – حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ حَدَّثَنَا شُعْبَةُ عَنْ هِشَامِ بْنِ زَيْدٍ قَالَ سَمِعْتُ أَنَسَ بْنَ مَالِكٍ يُحَدِّثُ

أَنَّ أُمَّهُ حِينَ وَلَدَتْ انْطَلَقُوا بِالصَّبِيِّ إِلَى النَّبِيِّ ﷺ لِيُحَنِّكَهُ قَالَ فَإِذَا النَّبِيُّ ﷺ فِي مِرْبَدٍ يَسِمُ غَنَمًا قَالَ شُعْبَةُ وَأَكْبَرُ عِلْمِي أَنَّهُ قَالَ فِي آذَانِهَا  

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Collected by Muslim
muslim:2119b – Muḥammad b. al-Muthanná > Muḥammad b. Jaʿfar > Shuʿbah > Hishām b. Zayd > Anas

So far as I know (he was cauterising) their ears.  

مسلم:٢١١٩b – حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ حَدَّثَنَا شُعْبَةُ عَنْ هِشَامِ بْنِ زَيْدٍ قَالَ سَمِعْتُ أَنَسًا يُحَدِّثُ

أَنَّ أُمَّهُ حِينَ وَلَدَتِ انْطَلَقُوا بِالصَّبِيِّ إِلَى النَّبِيِّ ﷺ يُحَنِّكُهُ قَالَ فَإِذَا النَّبِيُّ ﷺ فِي مِرْبَدٍ يَسِمُ غَنَمًا قَالَ شُعْبَةُ وَأَكْثَرُ عِلْمِي أَنَّهُ قَالَ فِي آذَانِهَا