Sunan an Nasai 5055
The Book of Adornment
أَخْبَرَنَا عَلِيُّ بْنُ حُجْرٍ، قَالَ حَدَّثَنَا عِيسَى بْنُ يُونُسَ، عَنْ هِشَامِ بْنِ حَسَّانَ، عَنِ الْحَسَنِ، عَنْ عَبْدِ اللَّهِ بْنِ مُغَفَّلٍ، قَالَ نَهَى رَسُولُ اللَّهِ صلى الله عليه وسلم عَنِ التَّرَجُّلِ إِلاَّ غِبًّا .
It was narrated that 'Abdullah bin Mughaffal said:"The Messenger of Allah [SAW] forbade combing one's hair, except every other day
Grading: Abu Ghuddah: Sahih · Al-Albani: Sahih · Zubair Ali Zai: Daif
Text from the public-domain hadith-api dataset. Numbering follows that dataset and can differ by a few from some printed editions — check the wording, not only the number.