Orejudo, S. et al. 2012. Levels of salivary cortisol and personality types of Grossarth-Maticek and Eysenck: A transcultural study. Journal of Psychopathology and Clinical Psychology   . 17, 2 (Feb. 2012), 137–150. DOI:https://doi.org/10.5944/rppc.vol.17.num.2.2012.11211.