Mazin Alqhazo and  Ayat Bani Rashaid,  Dopamine and Serotonin Levels in Blood Samples of Jordanian Children Who Stutter.   journal   = {International Journal of Medical and Health Sciences}, [online]. World Academy of Science, Engineering and Technology.
    September 2019, vol. 154(10). 441 - 445
    [viewed 20 November 2019]. Available from: https://publications.waset.org/pdf/10010818.