Bagg, T. C., & Stevens, M. E. (1961). Information selection systems retrieval replica copies: A-state-of-the-art report. U.S. Dept. of Commerce, National Bureau of Standards].

Bagg, Thomas C., and Mary Elizabeth Stevens. Information Selection Systems Retrieval Replica Copies: A-state-of-the-art Report. [Washington: U.S. Dept. of Commerce, National Bureau of Standards], 1961.

Bagg, Thomas C., and Mary Elizabeth Stevens. Information Selection Systems Retrieval Replica Copies: A-state-of-the-art Report. U.S. Dept. of Commerce, National Bureau of Standards], 1961.