The heat capacity of Bi2CuO4 has been measured from 5 to 350 K in an a
diabatic calorimeter. A long range ordering peak was found at 42.7 K d
ue to the establishment of three-dimensional antiferromagnetic order.
The magnetic entropy calculated for the anomaly corresponds to the the
oretical value for spin 1/2, DELTA S = R1n2, discarding the existence
of any lower dimensional magnetic contribution at a higher temperature
.