@article{IM2_2016_80_3_a1,
     author = {S. L. Gogyan},
     title = {Quasi-greedy property of subsystems of the multivariate {Haar} system},
     journal = {Izvestiya. Mathematics},
     pages = {481--488},
     year = {2016},
     volume = {80},
     number = {3},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_2016_80_3_a1/}
}