Le Khyu Zien

Publications in Math-Net.Ru

1. Homotopy classification of systems in the plane that are elliptic in the sense of Douglis and Nirenberg
   
   Dokl. Akad. Nauk SSSR, 244:4 (1979),  824–827
2. Homotopy classification of Petrovskii elliptic systems of equations in the plane
   
   Dokl. Akad. Nauk SSSR, 238:1 (1978),  26–28