Musnad Ahmad 27:1951

'Arim narrated to us, Hammad narrated to us, from Ayyub, from Nafi', from Ibn 'Umar, from the Prophet, peace and blessings of Allah be upon him, who said: "A man shall not sell over the sale of his brother, and he shall not propose over the proposal of his brother, unless he gives him permission." And perhaps he said: "He permits him."