A. Bilal, M. Sattar, and M. Khan, “Frequency Of Refractive Error in School Going Children Visiting Eye OPD with Complain of Headache and Eye Strain: Refractive Error in School Going Children”, PBMJ, vol. 5, no. 8, pp. 31–35, Aug. 2022, doi: 10.54393/pbmj.v5i8.678.