On the Charge Ordering Observed by Recent STM Experiments
  We present a perspective on the recent discoveries of possible charge ordering in underdoped Bi_2Sr_2CaCu_2O_{8+\delta} and Na_xCa_{2-x}CuO_2Cl_2 by high-resolution scanning tunnelling spectroscopy. 
Henry C. Fu, J. C. Davis, Dung-Hai Lee