APA (7th ed.) Zitazioa
Petkutė, R. (2012). English for sustainable environment: Study book. Technika.
Chicago Style (17th ed.) Zitazioa
Petkutė, Rūta. English for Sustainable Environment: Study Book. Vilnius: Technika, 2012.
MLA (9th ed.) Zitazioa
Petkutė, Rūta. English for Sustainable Environment: Study Book. Technika, 2012.
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