@article{CMUC_1976_17_3_a5,
     author = {Be\v{c}v\'a\v{r}, Jind\v{r}ich},
     title = {$K$-essential subgroups of abelian groups. {I}},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {481--492},
     year = {1976},
     volume = {17},
     number = {3},
     mrnumber = {0439951},
     zbl = {0344.20042},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1976_17_3_a5/}
}