BibTex format
@article{Ashbaugh:2016:10.1016/j.aim.2016.09.11,
author = {Ashbaugh, MS and Gesztesy, F and Laptev, A and Mitrea, M and Sukhtaiev, S},
doi = {10.1016/j.aim.2016.09.11},
journal = {Advances in Mathematics},
pages = {1108--1155},
title = {A bound for the eigenvalue counting function for Krein-von Neumann and Friedrichs extensions.},
url = {http://dx.doi.org/10.1016/j.aim.2016.09.11},
volume = {304},
year = {2016}
}