Abdullah ibn AbuBakr reported that he heard Urwah say: I entered upon Marwan ibn al-Hakam. We mentioned things that render the ablution void. Marwan said: Does it become void by touching the penis? Urwah replied: This I do not know. Marwan said: Busrah daughter of Safwan reported to me that she heard the Messenger of Allah ﷺ say: He who touches his penis should perform ablution. (Using translation from Abū Dāʾūd 181)   

أَنَّهَا سَمِعَتْ رَسُولَ اللَّهِ ﷺ يَقُولُ «يَتَوَضَّأُ الرَّجُلُ مِنْ مَسِّ الذَّكَرِ»  

[Machine] She heard the Prophet ﷺ saying, "Whoever touches his private parts should perform ablution." Abu Muhammad said, "This is more reliable in touching the private parts." And he said, "Ablution is more effective/strengthening."  

أَنَّهَا سَمِعَتِ النَّبِيَّ ﷺ يَقُولُ «مَنْ مَسَّ فَرْجَهُ فَلْيَتَوَضَّأْ» فَقَالَ أَبُو مُحَمَّدٍ هَذَا أَوْثَقُ فِي مَسِّ الْفَرْجِ وَقَالَ الْوُضُوءُ أَثْبَتُ