Open Science Research Excellence
Simon B. N. Thompson,  Saliva Cortisol and Yawning as a Predictor of Neurological Disease.   journal   = {International Journal of Psychological and Behavioral Sciences}, [online]. World Academy of Science, Engineering and Technology. April 2016, vol. 112(4). 211 - 214[viewed 19 July 2019]. Available from: http://waset.org/publications/10004285.