A critical point theorem and existence results for a nonlinear boundary value problem
2018 ◽
Vol 70
(3)
◽
pp. 410-421
◽
1978 ◽
Vol 78
(2)
◽
pp. 375-383
◽
2017 ◽
Vol 42
◽
pp. 723-733
1991 ◽
Vol 162
(2)
◽
pp. 482-493
1995 ◽
Vol 117
(2)
◽
pp. 428-445
◽