《资治通鉴·唐纪·唐纪四十二》
现在征发长安、洛阳、关辅百姓到丰州疏浚渠道，经营屯田，算起来，所得到的不足以补赏所耗费的，而且关辅百姓不免流亡离散。这样做，是使京城辖区空虚，而对军事储备却毫无补益。 
今发两京、关辅人于丰州浚渠营田，计所得不补所费，而关辅之人不免流散，是虚畿甸而无益军储也。 
Conscripting people from Chang'an, Luoyang, and Guanzhong to Fengzhou to dredge canals and cultivate garrison land, the income was far from enough to replenish the expenditures. In addition, people from Guanzhong inevitably fled and dispersed.  Doing this would weaken the capital region, but it did not benefit military supplies at all. 