Viliam Donic of Pavol Jozef Šafárik University in Košice, Košice with expertise in Sleep Medicine is on ResearchGate. PhD. - obtained in 1983, at Comenius University Bratislava after viva of the thesis ” Respiratory changes caused by severe acute hypoxia in cats, their characterization and some possibilities of its correction ”. Assoc. Prof in normal and pathological physiology. Thesis “Sleep apnea treatment by non invasive ventilation”