@article{VMUMM_1991_2_a0,
     author = {\`E. S. Belinskii and \`E. M. Galeev},
     title = {On the least norm value of mixed derivatives of trigonometric polynomials with a given number of harmonics},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {3--7},
     publisher = {mathdoc},
     number = {2},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1991_2_a0/}
}