@article{10_1007_s10587_014_0134_5,
     author = {Beasley, LeRoy B. and Song, Seok-Zun and Jun, Young Bae},
     title = {Linear operators that preserve graphical properties of matrices: isolation numbers},
     journal = {Czechoslovak Mathematical Journal},
     pages = {819--826},
     publisher = {mathdoc},
     volume = {64},
     number = {3},
     year = {2014},
     doi = {10.1007/s10587-014-0134-5},
     mrnumber = {3298562},
     zbl = {06391527},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.1007/s10587-014-0134-5/}
}