أَخْبَرَنَا أَحْمَدُ بْنُ الأَزْهَرِ، قَالَ حَدَّثَنَا رَوْحُ بْنُ عُبَادَةَ، قَالَ حَدَّثَنَا زَكَرِيَّا بْنُ إِسْحَاقَ، قَالَ حَدَّثَنَا عَمْرُو بْنُ دِينَارٍ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، أَنَّ رَجُلاً، قَالَ يَا رَسُولَ اللَّهِ إِنَّ أُمَّهُ تُوُفِّيَتْ أَفَيَنْفَعُهَا إِنْ تَصَدَّقْتُ عَنْهَا قَالَ ‏"‏ نَعَمْ ‏"‏‏.‏ قَالَ فَإِنَّ لِي مَخْرَفًا فَأُشْهِدُكَ أَنِّي قَدْ تَصَدَّقْتُ بِهِ عَنْهَا‏.‏

It was narrated from Ibn 'Abbas that a man said: "O Messenger of Allah, my mother died; will it benefit her if I give in charity on her behalf?" He said: "Yes." He said: "I have a garden and I ask you to bear witness that I am giving it in charity on her behalf." Translation Not Available

Book Ref: Sunan An Nisai Book 30 Hadith 3655
Web Ref:  Sunan An Nisai Vol 4 Book 30 Hadith 3685