%0 Journal Article %A H. Brzeskwiniewicz %T On the basic contrasts in PBIB designs %J Applicationes Mathematicae %D 1991 %P 335-341 %V 21 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/am-21-3-335-341/ %R 10.4064/am-21-3-335-341 %G en %F 10_4064_am_21_3_335_341