References
- Codres , HO . 1956 . Über die Randwertaufgabe bei quasilinearen Differentialgleichungen zweiter Ordnung in mehr als zwei Variablen. . Mathematische Annalen , 131 : 278 – 312 .
- Alkhutov Yu , A and Mamedov , IT . 1988 . The first boundary value problem for nondivergence second order parabolic equations with discontinuous coefficients. . Mathematical USSR Sbornik , 59 : 471 – 495 .
- Ladyshenskaja , OA and Uraltseva , NN . 1968 . Linear and Quasilinear Elliptic Equations , New York : Academic Press .
- Wen , GC and Begehr , H . 1990 . Boundary Value Problems for Elliptic Equations and Systems , Harlow: : Longman Scientific and Technical .
- Wen , GC and Chen , D . 2005 . Oblique derivative problems for nonlinear elliptic equations of second order with measurable coefficients in high dimensional domains . Nonlinear Sciences and Numerical Simulation , 10 : 559 – 570 .
- Hua , LK , Lin , W and Wu , TC . 1985 . Second Order Systems of Partial Differential Equations in the Plane , London : Pitman .