@article{SF_1974__9_134064,
     author = {J. Ad\'amek and V. Koubek and J. Reiterman},
     title = {On the existence of special homogeneous monoids.},
     journal = {Semigroup forum},
     pages = {95--101},
     year = {1974},
     volume = {9},
     zbl = {0303.20050},
     url = {http://geodesic.mathdoc.fr/item/SF_1974__9_134064/}
}