مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2299
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn ‘Abbas (رضي الله عنه) that The Messenger of Allah(ﷺ) said: “None of you should prevent his brother from fixing a piece of wood to his wall."
Musnad Ahmad 2307Its isnad hasan]