Issue No.02 - February (1981 vol.14)
The Nebula architecture of the military computer family provides, through carefully controlled visibility properties, both the flexibility to incorporate hardware advances and compatibility among family members.
W.B. Dietz, F.E. Ward, "Nebula: A New Architecture and its Relationship to Computer Hardware", Computer, vol.14, no. 2, pp. 35-41, February 1981, doi:10.1109/C-M.1981.220332