@article{Yuichiro Kobayashi2017, title={Investigating the Chronological Variation of Popular Song Lyrics ThroughLexical Indices}, author={Yuichiro Kobayashi and Misaki Amagasa and Takafumi Suzuki}, journal={Journal of the Japanese Association for Digital Humanities}, volume={2}, number={1}, pages={90-107}, year={2017}, doi={10.17928/jjadh.2.1_90} }