APA (7th ed.) Zitazioa
Ewing, G. M. Calculus of Varitions with Applications. Dover.
Chicago Style (17th ed.) Zitazioa
Ewing, George M. Calculus of Varitions with Applications. Nueva York, EUA: Dover.
MLA (9th ed.) Zitazioa
Ewing, George M. Calculus of Varitions with Applications. Dover.
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