Hatfield, N. J. (1978). Basic market, research techniques for transit systems. U.S. Department of Commerce.
Chicago-viite (17. p.)Hatfield, Nancy J. Basic Market, Research Techniques for Transit Systems. Austin: U.S. Department of Commerce, 1978.
MLA-viite (9. p.)Hatfield, Nancy J. Basic Market, Research Techniques for Transit Systems. U.S. Department of Commerce, 1978.
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