title: [The onset and character of menstruation in Bulgarian girls].
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002031:Bulgaria; D002648:Child; D005260:Female; D006801:Humans; D008572:Menarche; D008598:Menstruation; D008599:Menstruation Disturbances / Q000503:physiopathology; D011627:Puberty; D012189:Retrospective Studies; D012621:Seasons
vernacular_title: Beginn und Charakter der Menstruation bei den bulgarischen Mädchen