What is "hasanaginica"

Hasanaginica, less commonly ''Asanaginica, (first published as "The Mourning Song of the Noble Wife of the Hasan Aga'''") is a South Slavic folk ballad, created during the period of 1646–49, in the region of Imotski (in modern Croatia), which at the time was a part of the Bosnia Eyalet of the Ottoman Empire.