@article{ZR_1951_Knj_1_1_a8,
     author = {Vojislav G. Avakumovi\'c},
     title = {\"Uber {Geschlossene} {Kurven} auf der {Kugel}},
     journal = {Zbornik radova},
     pages = {101 - 108},
     publisher = {mathdoc},
     volume = {Knj. 1},
     number = {1},
     year = {1951},
     url = {http://geodesic.mathdoc.fr/item/ZR_1951_Knj_1_1_a8/}
}