It seems you are referring to a section from the classical Hanafi fiqh text (full title: Al-Hidayah fi Sharh Bidayat al-Mubtadi ), specifically the "Kitab al-Buyu" (Book of Sales/Transactions).
It seems you are referring to a section from the classical Hanafi fiqh text (full title: Al-Hidayah fi Sharh Bidayat al-Mubtadi ), specifically the "Kitab al-Buyu" (Book of Sales/Transactions).