The find suggests that the entire area was once modified , probably under the orders of sneferu and other pharaohs of the old kingdom ( quaternary international , doi : 10.1016/j.quaint.2012.02.045 ) .
Optical properties of doped quaternary ammonium salt kdp crystals .
季氨盐对kdp晶体的光学特性影响。
Dr ruddiman argues , in quaternary science reviews , that with vast tranches of land at their disposal and only unrefined agricultural techniques , early farmers had no incentive to maximise the potential of the land they farmed .