Determination of low levels of benzodiazepines and their metabolites in urine by hollow-fiber liquid-phase microextraction (LPME) and gaschromatography–mass spectrometry (GC–MS) - Bairros, André Valle de; Almeida, Rafael Menck de; Pantaleão, Lorena; Barcellos, Thiago; Silva, Sidnei Moura e; Yonamine, Maurício (Journal of Chromatography B, 2015)