Sowmya Vajjala Ivana Lucic OneStopEnglish corpus: A new corpus for automatic readability assessment and text simplification. 297-304 2018 BEA@NAACL-HLT https://doi.org/10.18653/v1/w18-0535 https://aclanthology.org/W18-0535/ conf/bea/2018 db/conf/bea/bea2018.html#VajjalaL18