@article{700752,
     title = {On a mechanism of choosing morphisms in concrete categories},
     booktitle = {General Topology and its Relations to Modern Analysis and Algebra},
     series = {GDML\_Books},
     publisher = {Academia Publishing House of the Czechoslovak Academy of Sciences},
     address = {Praha},
     year = {1972},
     pages = {263-265},
     mrnumber = {MR0349798},
     zbl = {0319.18002},
     url = {http://dml.mathdoc.fr/item/700752}
}

Kučera, L.; Pultr, A. On a mechanism of choosing morphisms in concrete categories, dans General Topology and its Relations to Modern Analysis and Algebra, GDML_Books,  (1972), pp. 263-265. http://gdmltest.u-ga.fr/item/700752/