共 11 条
[1]
Sturm-Liouville problems whose leading coefficient function changes sign
[J].
CANADIAN JOURNAL OF MATHEMATICS-JOURNAL CANADIEN DE MATHEMATIQUES,
2003, 55 (04)
:724-749
[2]
Courant R., 1989, Methods of mathematical physics, V1
[7]
Kong Q, 2000, P ROY SOC EDINB A, V130, P561
[8]
Kong QK, 2008, P ROY SOC EDINB A, V138, P323