Al-Kāfi - Volume 6 > The Under arms
Hadith #2

مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ ابْنِ فَضَّالٍ عَنْ عَلِيِّ بْنِ عُقْبَةَ عَنْ أَبِي كَهْمَسٍ قَالَ قَالَ أَبُو عَبْدِ اللَّهِ ( عليه السلام ) نَتْفُ الْإِبْطِ يُضْعِفُ الْمَنْكِبَيْنِ وَ كَانَ أَبُو عَبْدِ اللَّهِ ( عليه السلام ) يَطْلِي إِبْطَهُ .

2. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from ibn Faddal from Ali ibn ‘Uqbah from abu Kahmas who has said the following: “Abu ‘ Abd Allah, ‘Alayhi al-Salam, has said, ‘Pulling out the hairs of the underarms weakens the shoulders.’ Abu ‘Abd Allah, ‘Alayhi al-Salam, applied lime paste as a hair remover.’”