APA-viite (7. p.)
Khalid, A. Water supply in republic of Yemen. Modern state and directions of perfection.
Chicago-viite (17. p.)Khalid, Abdo. Water Supply in Republic of Yemen. Modern State and Directions of Perfection.
MLA-viite (8. p.)Khalid, Abdo. Water Supply in Republic of Yemen. Modern State and Directions of Perfection.
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