Hadith
أَخْبَرَنَا أَحْمَدُ بْنُ سُلَيْمَانَ، قَالَ حَدَّثَنَا يَعْلَى، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ أَبِي الزُّبَيْرِ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ لاَ تَحِلُّ الرُّقْبَى وَلاَ الْعُمْرَى فَمَنْ أُعْمِرَ شَيْئًا فَهُوَ لَهُ وَمَنْ أُرْقِبَ شَيْئًا فَهُوَ لَهُ .
(A different chain) from Sufyan, from Abu Az-Zubair, from Tawus, from Ibn 'Abbas, who said:"Ruqba and 'Umra are not permissible; whoever is given something on the basis of 'Umra, it is his, and whoever is given something on the basis of Ruqba, it is his
Sahih · Abu Ghuddah
Sunan an-Nasa'i 3712 ·Book 33, Hadith 7·Also available on sunnah.com·