APA (7th ed.) Zitazioa
Swindoll, R. C. (1981). Improving your serve. Word Publishing.
Chicago Style (17th ed.) Zitazioa
Swindoll, R. Charles. Improving Your Serve. Dallas: Word Publishing, 1981.
MLA (9th ed.) Zitazioa
Swindoll, R. Charles. Improving Your Serve. Word Publishing, 1981.
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