وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ قَالَ كُنَّا فِي زَمَانِ رَسُولِ اللَّهِ صلى الله عليه وسلم نَبْتَاعُ الطَّعَامَ فَيَبْعَثُ عَلَيْنَا مَنْ يَأْمُرُنَا بِانْتِقَالِهِ مِنَ الْمَكَانِ الَّذِي ابْتَعْنَاهُ فِيهِ إِلَى مَكَانٍ سِوَاهُ قَبْلَ أَنْ نَبِيعَهُ ‏.‏

Yahya related to me from Malik from Nafi that Abdullah ibn Umarsaid, "In the time of the Messenger of Allah, may Allah bless him andgrant him peace, we used to buy food. He sent orders for us to moveour purchases from the place in which we purchased them to anotherplace before we re-sold them." Translation Not Available

Book Ref: Muwatta Imam Malik Book 31 Hadith 1334
Web Ref:  Muwatta Imam Malik Book 31 Hadith 42