Ems, E. (1988). Economics of public information systems. Dept. of Economics, University of Stockholm.
Chicago-viite (17. p.)Ems, Emil. Economics of Public Information Systems. Stockholm: Dept. of Economics, University of Stockholm, 1988.
MLA-viite (8. p.)Ems, Emil. Economics of Public Information Systems. Dept. of Economics, University of Stockholm, 1988.
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