أَخْبَرَنَا أَحْمَدُ بْنُ حَرْبٍ، قَالَ حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنْ حَجَّاجٍ، عَنْ أَبِي الزُّبَيْرِ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسِ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ الْعُمْرَى جَائِزَةٌ لِمَنْ أُعْمِرَهَا وَالرُّقْبَى جَائِزَةٌ لِمَنْ أُرْقِبَهَا وَالْعَائِدُ فِي هِبَتِهِ كَالْعَائِدِ فِي قَيْئِهِ ‏"‏ ‏.‏

Hajjaj narrated from Abu Az-Zubair, from Tawus, from Ibn 'Abbas, who said: "The Messenger of Allah said: 'Umra (life-long gift) is permissible for the one to whom it is given, and Ruqba is permissible to the one to whom it is given, and the one who takes back his gift is like the one who goes back to his vomit.'" Translation Not Available

Book Ref: Sunan An Nisai Book 33 Hadith 3710
Web Ref:  Sunan An Nisai Vol 4 Book 33 Hadith 3740