@article{NUMA_1969__13_131916,
     author = {P. LANCASTER and M.V. PATTABHIRAMAN},
     title = {Spectral {Properties} of a {Polynomial} {Operator.}},
     journal = {Numerische Mathematik},
     pages = {247--259},
     publisher = {mathdoc},
     volume = {13},
     year = {1969},
     zbl = {0177.17202},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1969__13_131916/}
}