@article{JRAM_1989__399_153153,
     author = {Rainer Hempel},
     title = {On the asymptotic distribution of the eigenvalue branches of the {Schr\"odinger} operator {H...} {W} in a spectral gap of {H.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {38--59},
     publisher = {mathdoc},
     volume = {399},
     year = {1989},
     zbl = {0681.35066},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1989__399_153153/}
}