@article{VMUMM_1993_2_a0,
     author = {Nguen Khak Tkhan'},
     title = {Representation of natural numbers by a cubic form in seven variables},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {3--7},
     publisher = {mathdoc},
     number = {2},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1993_2_a0/}
}