《明史·志·卷四十八》
所有军队戍守之处，如有转运供应不上，便设屯以充实军队储备。
凡军马守镇之处，其有转运不给，则设屯以益军储。
In all places where the army is garrisoned, if there are any problems with transportation, depots will be set up to replenish the army reserves.