A sensitive and robust lc-ms/ms method with monolithic column and electrospray ionization for the quantitation of efavirenz in human plasma: application to a bioequivalence study oleh Danilo Cesar Galindo Bedor, Jose Homero de Souza Filho, Virna Ligiane Souza Ramos, Talita Mota Gonçalves, Carlos Eduardo Miranda de Sousa, Davi Pereira de Santana