Is La1.85Y0.15CuO4 an oxygen-doped cuprate superconductor?
  We report resistivity, Hall effect, Nernst effect, and magnetoresistance measurements on T'-phase La1.85Y0.15CuO (LYCO) films prepared by pulsed laser deposition under different oxygen conditions. Our results show that superconductivity in LYCO originates from an oxygen-doped Mott-like insulator and not from a weakly correlated, half-filled band metal as proposed previously. 
W. Yu, B. Liang, P. Li, S. Fujino, T. Murakami, I. Takeuchi, R. L.   Greene