@article{articlef5fc5d10,
title   = {Modified graphene-silica as a sorbent for in-tube solid-phase microextraction coupled to liquid chromatography-tandem mass spectrometry: Determination of xanthines in coffee beverages},
author = {Mejía-Carmona, Karen and Lanças, Fernando Mauro},
year = {2020},
doi = {10.1016/j.chroma.2020.461089},
journal   = {Journal of Chromatography A}
}