Variational methods for boundary value problems, for systems of elliptic equations / M.A. Lavrentev,Authorized translation from the Russian edited by J.R.M. Radok. Variat͡sionnyĭ metod v kraevykh zadachakh dli͡a sistem uravneniĭ ėllipticheskogo tipa. English Lavrentʹev, M. A. (Mikhail Alekseevich), 1900-1980. Calculus of variations. Conformal mapping. Boundary value problems. Fluid dynamics. QA316 .L363 517.36 LAV Groningen : Noordhoff. Ltd., c1963 c1963 1963 Text 150 p. : eng engrus