مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3714
Musnad of Abdullah bin Mas'ood
It was narrated that Ibn Mas'ood (رضي الله عنه) said: The Messenger of Allah (ﷺ) cursed the one who consumes riba, the one who pays it, the two who witness it, and the one who writes it down.
Musnad Ahmad 3737A saheeh hadeeth, Muslim (1597)]