@article{oai:repository.dl.itc.u-tokyo.ac.jp:00040359,
 author = {Tri, Nguyen Minh},
 issue = {3},
 journal = {Journal of mathematical sciences, the University of Tokyo},
 month = {},
 note = {application/pdf},
 pages = {567--587},
 title = {A bifurcation of multiple eigenvalues and eigenfunctions for boundary value problems in a domain with a small hole},
 volume = {1},
 year = {1994}
}