@article{UZERU_2011_1_a0,
     author = {V. Zh. Dumanyan},
     title = {On the boundedness of a class of the first order linear differential operators},
     journal = {Proceedings of the Yerevan State University. Physical and mathematical sciences},
     pages = {3--6},
     publisher = {mathdoc},
     number = {1},
     year = {2011},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UZERU_2011_1_a0/}
}