Obst, P. (2011). Age and gender comparisons of driving while sleepy: Behaviours and risk perceptions. Elsevier Ltd.
Chicago-viite (17. p.)Obst, Patricia. Age and Gender Comparisons of Driving While Sleepy: Behaviours and Risk Perceptions. Netherlands: Elsevier Ltd, 2011.
MLA-viite (8. p.)Obst, Patricia. Age and Gender Comparisons of Driving While Sleepy: Behaviours and Risk Perceptions. Elsevier Ltd, 2011.
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