Funk, W. J., & Lewis, N. (1970). 30 days to a more powerful vocabulary (Newly rev. by Norman Lewis.). Pocket Books.
Chicago Style aipamenaFunk, Wilfred John, and Norman Lewis. 30 Days to a More Powerful Vocabulary. Newly rev. by Norman Lewis. New York: Pocket Books, 1970.
MLA aipamenaFunk, Wilfred John, and Norman Lewis. 30 Days to a More Powerful Vocabulary. Newly rev. by Norman Lewis. Pocket Books, 1970.
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