@article{10_21136_CPM_1965_108645,
     author = {Zelinka, Bohdan},
     title = {Some inequalities concerning $\Pi$-isomorphisms},
     journal = {\v{C}asopis pro p\v{e}stov\'an{\'\i} matematiky},
     pages = {474--476},
     publisher = {mathdoc},
     volume = {090},
     number = {4},
     year = {1965},
     doi = {10.21136/CPM.1965.108645},
     mrnumber = {0190007},
     zbl = {0131.01203},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CPM.1965.108645/}
}