@article{MZM_1978_23_1_a7,
     author = {V. N. Konovalov},
     title = {Precise inequalities for norms of functions, third partial, second mixed, or directional derivatives},
     journal = {Matemati\v{c}eskie zametki},
     pages = {67--78},
     publisher = {mathdoc},
     volume = {23},
     number = {1},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1978_23_1_a7/}
}