Variational Methods in Differential Equations
2009 ◽
Vol 35
(1-2)
◽
pp. 323-340
◽
2005 ◽
Vol 22
(2)
◽
pp. 227-257
◽
2017 ◽
Vol 10
(03)
◽
pp. 990-1003
1984 ◽
pp. 181-192
◽