Sahih al-Bukhari 2245
Narrated Muhammad bin Abi Al-Mujalid:
as above (446) and said, "We used to pay them in advance for wheat and barley (to be delivered later). 
Narrated Ash-Shaibani--"And also for oil."
Narrated Ash-Shaibani:

who said "We used to pay in advance for wheat barley and dried grapes."
حَدَّثَنَا إِسْحَاقُ، حَدَّثَنَا خَالِدُ بْنُ عَبْدِ اللَّهِ، عَنِ الشَّيْبَانِيِّ، عَنْ مُحَمَّدِ بْنِ أَبِي مُجَالِدٍ، بِهَذَا وَقَالَ فَنُسْلِفُهُمْ فِي الْحِنْطَةِ وَالشَّعِيرِ‏.‏ وَقَالَ عَبْدُ اللَّهِ بْنُ الْوَلِيدِ عَنْ سُفْيَانَ حَدَّثَنَا الشَّيْبَانِيُّ وَقَالَ وَالزَّيْتِ‏.‏ حَدَّثَنَا قُتَيْبَةُ حَدَّثَنَا جَرِيرٌ عَنِ الشَّيْبَانِيِّ وَقَالَ فِي الْحِنْطَةِ وَالشَّعِيرِ وَالزَّبِيبِ‏.‏