Issue No. 03 - July-September (1980 vol. 2)
<p>The relay calculator Z4 was designed by Konrad Zuse in Berlin during the last years of World War II. It occupies a unique place in the family of early digital computers. Some of the outstanding characteristics of the Z4 were use of the binary system with floating point, mechanical 2048-bit memory, and provision for intermediate data storage on punched tape.</p>
A. Speiser, "The Relay Calculator Z4," in IEEE Annals of the History of Computing, vol. 2, no. , pp. 242-245, 1980.