Rothamsted Experimental Station, Harpenden, Hertfordshire, England

Robinson [1966] gave a list of the parameters of balanced incomplete block designs with no more than 100 units and with the blocks arranged in two orthogonal groups of sets (rows and columns), each set in either group consisting of one or more complete replications of the treatments. Robinson also gave designs for two sets of parameters. Table 1 of the present note gives a design for each parameter set,