@article{1077476557,
author = {Putnam, C. R.},
title = {The comparison of spectra belonging to potentials with a
bounded difference},
journal = {Duke Math. J.},
volume = {18},
number = {1},
year = {1951},
pages = { 267-273},
language = {en},
url = {http://dml.mathdoc.fr/item/1077476557}
}
Putnam, C. R. The comparison of spectra belonging to potentials with a
bounded difference. Duke Math. J., Tome 18 (1951) no. 1, pp. 267-273. http://gdmltest.u-ga.fr/item/1077476557/