QT interval variability index and QT interval duration in different sleep stages : analysis of polysomnographic recordings in nonapneic male patientsViigimäe, Moonika; Karai, Deniss; Pirn, Peeter; Pilt, Kristjan; Meigas, Kalju; Kaik, JüriBioMed Research International2015 / art. 963028 https://doi.org/10.1155/2015/963028 Journal metrics at Scopus Article at Scopus Journal metrics at WOS Article at WOS