Bird, S., Klein, E., & Loper, E. (2009). Natural language processing with Python (First edition.). O'Reilly.
Chicago Style (17. basım) AtıfBird, Steven, Ewan Klein, ve Edward Loper. Natural Language Processing with Python. First edition. Beijing ; Cambridge, Mass.: O'Reilly, 2009.
MLA (8th ed.) AtıfBird, Steven, et al. Natural Language Processing with Python. First edition. O'Reilly, 2009.
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