Kayastha, P., S. Paudel, and R. K. Ghimire. “Ultrasound Measurement of Thyroid Isthmus Thickness in Clinically Euthyroid Subjects”. Nepalese Journal of Radiology, vol. 8, no. 2, Dec. 2018, pp. 26-29, doi:10.3126/njr.v8i2.22979.