TY  - BOOK
AU  - Gould,S.H
TI  - Variational methods for eigenvalue problems: introduction to the methods of rayleigh, ritz, weinstein & aronszajn
SN  - 9780486687124
U1  - 4.13+11.14 
PY  - 1995///
CY  - New York
PB  - Dover Publications
ER  -