@article{MZM_1984_35_2_a3,
     author = {V. M. Kadets and M. I. Kadets},
     title = {Conditions for convexity of the set of limits of {Riemann} sums of a vector-valued function},
     journal = {Matemati\v{c}eskie zametki},
     pages = {161--167},
     publisher = {mathdoc},
     volume = {35},
     number = {2},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1984_35_2_a3/}
}