Al-Kāfi

Hadith 187
wudu
2ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ ابْنِ فَضَّالٍ عَنِ ابْنِ بُكَيْرٍ عَنْ عُمَرَ بْنِ حَنْظَلَةَ قَالَ سَأَلْتُ أَبَا عَبْدِ الله (عَلَيْهِ الْسَّلام) عَنِ الْمَذْيِ فَقَالَ مَا هُوَ وَالنُّخَامَةُ إِلاَّ سَوَاءٌ.
2. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from ibn Faddal from ibn Bukayr from ‘Umar ibn Hanzalah who has said the following: “I once asked abu ‘Abd Allah (a.s.), about al-Madhiy. He (the Imam) said, ‘It is only like nasal mucus. They are very similar.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī