Abu Zabyan says that Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) used to recite this word as: "So mention the name of Allah over them while they stand (sawafin)" [Surah al-Hajj: 36], and he would say: (It means) tied, standing on three legs. Then he would say: 'Bismillahi wallahu akbar, Allahumma minka wa laka' (In the name of Allah, and Allah is the Greatest; O Allah, it is from You and for You). The narrator says: He was asked about their hides, and he said: One may give them in charity or benefit from them oneself.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10217