References
- Sze , SM . 1969 . Physics of Semiconductor Devices , Berlin : Wiley .
- Dacorogna , B . 1989 . Direct Methods in the Calculus of Variations , Basel : Springer-Verlag .
- Pucci , P and Serrin , J . 2007 . The Maximum Principle , New York : Birkhäuser .
- Philips, Components and Materials, Philips Technical Manual, August 1979