https://uomosul.edu.iq/science/%d8%a7%d9%84%d8%b3%d9%8a%d8%af-%d8%b1%d8%a6%d9%8a%d8%b3-%d9%82%d8%b3%d9%85-%d8%a7%d9%84%d9%81%d9%8a%d8%b2%d9%8a%d8%a7%d8%a1-%d9%83%d9%84%d9%8a%d8%a9-%d8%a7%d9%84%d8%b9%d9%84%d9%88%d9%85-%d9%8a%d8%ad-2/