25. SOME FACTORS RELATED TO SLEEP DISORDERS IN HEAD AND NECK CANCER PATIENTS AT K HOSPITAL . YHCĐ [Internet]. 2025 May 22 [cited 2026 Sept. 9];66(CĐ7-HNKH Bệnh viện K). Available from: https://tapchiyhcd.vn/index.php/yhcd/article/view/2406