Infrared properties of electron-doped cuprates: Tracking normal-state gaps and quantum critical behavior in Pr <sub> 2 − <i>x</i> </sub> Ce <sub> <i>x</i> </sub> CuO <sub>4</sub>A. Zimmers, C. C. Homes, R. P. S. M. Lobo et al.|Europhysics Letters (EPL)|2005Cited by 76