@article{10_21136_AM_1981_103913,
     author = {Rektorys, Karel and Vosp\v{e}l, Zden\v{e}k},
     title = {On a method of two-sided eigenvalue estimates for elliptic equations of the form $Au-\lambda Bu=0$},
     journal = {Applications of Mathematics},
     pages = {211--240},
     publisher = {mathdoc},
     volume = {26},
     number = {3},
     year = {1981},
     doi = {10.21136/AM.1981.103913},
     mrnumber = {0615608},
     zbl = {0474.65080},
     language = {en},
     url = {https://geodesic-test.mathdoc.fr/articles/10.21136/AM.1981.103913/}
}