@article{articlec7e15c5a,
title   = {Confirmation of cocaine exposure by gas chromatography-mass spectrometry of urine extracts after methylation of benzoylecgonine},
author = {Yonamine, Maurício and Silva, Ovandir Alves},
year = {2002},
doi = {10.1016/s0378-4347(01)00516-3},
journal   = {Journal of Chromatography B}
}