مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3481
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn ‘Abbas (رضي الله عنه) that A man said: O Messenger of Allah, my mother has died; will it benefit her if I give charity on her behalf? He said: "Yes." He said: I have a garden; I ask you to bear witness that I have given it in charity on her behalf.
Musnad Ahmad 3504Its isnad is saheeh, al-Bukhari (2770)]