Approximation of elliptic boundary-value problems - paperback, good condition

Variational Methods For Boundary Value Problems For Systems Of Elliptic Equation

Numerical Methods for Two-Point Boundary Value Problems by Herbert B. Keller

Variational Methods for Boundary Value Problems: for Systems of Elliptic Equ...

Numerical Methods for Two-Point Boundary-Value Problems, Keller, Herbert B., 978

Numerical Approximation Methods for Elliptic Boundary Value Problems: Finite and

Approximation of Functions Theory and Numerical Methods by gunter Meinardus HC

Variational Methods for Boundary Value Problems for Systems of Elliptic Equation