@article{NCD_2011_18_a4,
     author = {Nikolay Kirov},
     title = {Digitization of {Bulgarian} {Folk} {Songs} with {Music,} {Notes} and {Text}},
     journal = {Review of the National Center for Digitization},
     pages = {35 },
     publisher = {mathdoc},
     volume = {18},
     year = {2011},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/NCD_2011_18_a4/}
}