Winter needn't be the SAD season.
Weir
E
E
D002170:Canada / Q000453:epidemiology; D002940:Circadian Rhythm; D006801:Humans; D008550:Melatonin / Q000097:blood / Q000627:therapeutic use; D010789:Phototherapy; D016574:Seasonal Affective Disorder / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*
D008550:Melatonin