@article{MZ_1983__182_173286,
     author = {C.V. Coffman and M.M. Marcus and V.J. Mizel},
     title = {On {Green's} {Function} and {Eigenvalues} of {Nonuniformly} {Elliptic} {Boundary} {Value} {Problems.}},
     journal = {Mathematische Zeitschrift},
     pages = {321--326},
     publisher = {mathdoc},
     volume = {182},
     year = {1983},
     zbl = {0489.35060},
     url = {http://geodesic.mathdoc.fr/item/MZ_1983__182_173286/}
}