Musannaf Ibn Abi Shayba 13:1119

Abu Bakr narrated to us, he said: Abd al-A’la ibn Abd al-A’la narrated to us, from Ma’mar, from al-Zuhri, that Ibn Umar and Zayd ibn Thabit used to see no harm in buying provisions (rizq) when the *qutut*—which are the *sakak* (documents/vouchers)—were issued. And they used to say: Do not sell it until you take possession of it.