00458nam a2200169Ia 4500 516 G427.DP Ghoussoub, Nassif Duality and perturbation methods in critical point theory Cambridge Cambridge University Press 1991 xviii, 258p. Index. Appendix Cambridge tracts in Mathematics v.107 0 0 0 0 ISI ISI 1998-09-21 0 516 G427.DP DP22254 2019-02-14 00:00:00 2019-02-14 BK 12404 12404 12404