@article{GDZPPN002346206, title = {Homogeneous Universal Relational Systems.}, journal = {Mathematica Scandinavica}, volume = {8}, year = {1960}, pages = {137-142}, zbl = {0173.00505}, url = {http://dml.mathdoc.fr/item/GDZPPN002346206} }
Jonsson, B. Homogeneous Universal Relational Systems.. Mathematica Scandinavica, Tome 8 (1960) pp. 137-142. http://gdmltest.u-ga.fr/item/GDZPPN002346206/