Sahih Muslim 10983
In-book no 3706وَحَدَّثَنَاهُ ابْنُ أَبِي عُمَرَ، حَدَّثَنَا عَبْدُ الْوَهَّابِ، عَنْ أَيُّوبَ، بِهَذَا الإِسْنَادِ غَيْرَ أَنَّهُ قَالَ " مَنِ اشْتَرَى مِنَ الْغَنَمِ فَهُوَ بِالْخِيَارِ " .
Ayyub narrated with the same chain of transmitters but with this change of words: " He who buys a goat has the option...."