مُسْنَدُ أَحْمَدَ
Musnad Ahmad 4012
Musnad of Abdullah bin Mas'ood
It was narrated that 'Abdullah said. The Messenger of Allah (ﷺ) said: “Whoever dies not associating anything with Allah will enter Paradise.” And I say: Whoever dies associating something with Allah will enter Hell.
Musnad Ahmad 4038Its isnad is saheeh, al-Bukhari (1238) and Muslim (92)]