Let A1 and A2 be the following arrays over Z_3 X Z_5 X Z_5:


  A1 =  000       A2 = 200 000 000 100 000 100 100
        000            023 144 113 104 243 003 144
        000            132 211 140 030 104 241 012
        000            024 131 202 001 240 122 000
        000            112 223 031 142 210 143 244
        000            014 044 241 130 131 200 240
        000            044 201 233 232 002 212 142
        000            242 241 231 122 130 002 242

and let A3 be the 8X7 array obtained by interchanging rows i and 9-i
(1 <= i <= 4) in A2. The required (75,8,1) difference matrix is then
obtained by adding the following vectors to each column of [A1|A2|A3]
for 0 <= x <= 4: [(0,0,x),(0,x,0),(0,x,2x),(0,2x,2x),(0,3x,3x),(0,4x,3x),
(0,4x,0),(0,0,4x)].


-- Julian Abel.