The Book of Transactions
حَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، أَخْبَرَنَا رَوْحٌ، حَدَّثَنَا ابْنُ جُرَيْجٍ، حَدَّثَنِي أَبُو الزُّبَيْرِ، أَنَّهُ سَمِعَ جَابِرَ بْنَ عَبْدِ اللَّهِ، يَقُولُ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَقُولُ " إِذَا ابْتَعْتَ طَعَامًا فَلاَ تَبِعْهُ حَتَّى تَسْتَوْفِيَهُ " .Jabir b. Abdullah (Allah be pleased with them) reported Allah's Messenger (ﷺ) as saying:When you purchase foodgrains, do not sell them until you have taken possession of them
From Sahih Muslim, whose reports the scholars accept as authentic.