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Lua i Stíl Chicago (17ú heag.)Kečkić, Jovan D. A Differential Operator and Its Applications to Partial Differential Equations and Nonanalytic Functions. [Beograd: Univerzitet, Elektrotehnički fakultet], 1970.
Lua MLA (8ú heag.)Kečkić, Jovan D. A Differential Operator and Its Applications to Partial Differential Equations and Nonanalytic Functions. Univerzitet, Elektrotehnički fakultet], 1970.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.