Amalina, Nurika, and Erna Setiawati. 2021. “Effectiveness of Deep Cervical Flexor (DCF) Exercise on Neck Functional Scores in Helicopter Crew With Mechanical Neck Pain”. Surabaya Physical Medicine and Rehabilitation Journal 3 (2):71-76. https://doi.org/10.20473/spmrj.v3i2.24272.