Haruo Okabayashi,  The Relationship between Fluctuation of Biological Signal: Finger Plethysmogram in Conversation and Anthropophobic Tendency.   journal   = {International Journal of Humanities and Social Sciences}, [online]. World Academy of Science, Engineering and Technology.
    September 2016, vol. 117(9). 3228 - 3232
    [viewed 23 January 2020]. Available from: https://publications.waset.org/pdf/10005707.