WASET
    Soo- Young Ye and  Dong-Hyun Kim,  Development of Position Changing System for Obstructive Sleep Apnea Patient using HRV.   journal   = {International Journal of Biomedical and Biological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2012, vol. 67(7). 330 - 332
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/15105.