Halacy, D. (1968). Century 21 : your life in the year 2001 and: Beyond. Macrae Smith.
Chicago-čujuhus (17. p.)Halacy, D.S. Century 21 : Your Life in the Year 2001 and: Beyond. Philadelphia: Macrae Smith, 1968.
MLA-čujuhus (9. p.)Halacy, D.S. Century 21 : Your Life in the Year 2001 and: Beyond. Macrae Smith, 1968.
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