Sunan Ibn Majah 504
سنن ابن ماجه#504Sahihحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا هُشَيْمٌ، عَنْ يَزِيدَ بْنِ أَبِي زِيَادٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي لَيْلَى، عَنْ عَلِيٍّ، قَالَ سُئِلَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ عَنِ الْمَذْىِ فَقَالَ " فِيهِ الْوُضُوءُ وَفِي الْمَنِيِّ الْغُسْلُ " .
It was narrated that 'Ali said:"The Messenger of Allah was asked about prostatic fluid and he said: 'For that ablution (is necessary), and for semen, bath is necessary
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Shuaib Al ArnautDaif
Zubair Ali ZaiDaif
In-book reference: 1:238