@article{DMPS_2012_32_1-2_a4,
     author = {Syn\'owka-Bejenka, Ewa and Zontek, Stefan},
     title = {On optimality of the orthogonal block design},
     journal = {Discussiones Mathematicae. Probability and Statistics},
     pages = {59--68},
     publisher = {mathdoc},
     volume = {32},
     number = {1-2},
     year = {2012},
     zbl = {06248587},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/DMPS_2012_32_1-2_a4/}
}