@article{10_21136_CMJ_1965_100685,
     author = {Dole\v{z}al, V\'aclav},
     title = {An extension of {Popov's} method for vector-valued nonlinearities},
     journal = {Czechoslovak Mathematical Journal},
     pages = {436--453},
     publisher = {mathdoc},
     volume = {15},
     number = {3},
     year = {1965},
     doi = {10.21136/CMJ.1965.100685},
     mrnumber = {0179564},
     zbl = {0147.10505},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1965.100685/}
}