Kensho Takahashi and  Ko Watanabe and  Takashi Kaburagi and  Hiroshi Tanaka and  Kajiro Watanabe and  Yosuke Kurihara,  A Novel NIRS Index to Evaluate Brain Activity in Prefrontal Regions While Listening to First and Second Languages for Long Time Periods.   journal   = {International Journal of Cognitive and Language Sciences}, [online]. World Academy of Science, Engineering and Technology.
    February 2015, vol. 99(3). 235 - 241
    [viewed 05 June 2020]. Available from: