Sanches RF, Crippa JA de S, Hallak JEC, Araújo D, Zuardi AW. Proton magnetic resonance spectroscopy of the frontal lobe in schizophrenics: a critical review of the methodology . Rev. Hosp. Clín. 2004;59(3):145-152. doi:10.1590/S0041-87812004000300010