2026-04-08T20:57:55Zhttps://repository.sdu.edu.kz/server/oai/requestSDU University Repositoryhttps://repository.sdu.edu.kz/server/oai/request2.0repository@sdu.edu.kz2022-06-27T12:18:34ZtransientYYYY-MM-DDThh:mm:ssZ oai repository.sdu.edu.kz : oai:repository.sdu.edu.kz:123456789/1234