@article{articlef59559aa,
title   = {Automatic question classifiers: a systematic review},
author = {Silva, Valtemir Alencar e and Pinto, Ig Ibert Bittencourt Santana and Maldonado, José Carlos},
year = {2019},
doi = {10.1109/TLT.2018.2878447},
journal   = {IEEE Transactions on Learning Technologies}
}