[Tiráž a obálka]
Dokonalé a spriatelené čísla, GDML_Books, (1969), p. [50]-[53] / Harvested from
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@inbook{403673,
     title = {[Tir\'a\v z a ob\'alka]},
     booktitle = {Dokonal\'e a spriatelen\'e \v c\'\i sla},
     series = {GDML\_Books},
     publisher = {Mlad\'a fronta},
     address = {Praha},
     year = {1969},
     pages = {[50]-[53]},
     url = {http://dml.mathdoc.fr/item/403673}
}

 (éd.). [Tiráž a obálka], dans Dokonalé a spriatelené čísla, GDML_Books,  (1969), pp. [50]-[53]. http://gdmltest.u-ga.fr/item/403673/