@article{10_21136_MB_2002_133959,
     author = {Do\v{s}l\'y, Ond\v{r}ej},
     title = {The {Picone} identity for a class of partial differential equations},
     journal = {Mathematica Bohemica},
     pages = {581--589},
     publisher = {mathdoc},
     volume = {127},
     number = {4},
     year = {2002},
     doi = {10.21136/MB.2002.133959},
     mrnumber = {1942643},
     zbl = {1074.35521},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.2002.133959/}
}