@article{MZM_1976_19_6_a7,
     author = {E. K. Godunova and V. I. Levin},
     title = {A~cyclic sum with 12 terms},
     journal = {Matemati\v{c}eskie zametki},
     pages = {873--885},
     publisher = {mathdoc},
     volume = {19},
     number = {6},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1976_19_6_a7/}
}