Lin, M.-L., H.-W. Chiu, Z.-M. Shih, P.-Y. Lee, P.-Z. Li, C.-H. Guo, Y.-J. Luo, S.-C. Lin, K.-Y. Lin, Y.-M. Hsu, A. Pang, and W. Pang. “Two Transcutaneous Stimulation Techniques in Shoulder Pain: Transcutaneous Pulsed Radiofrequency (TPRF) Vs. Transcutaneous Electrical Nerve Stimulation (TENS): Detailed Study”. Emerging Research in Medical Sciences Vol. 4, Apr. 2020, pp. 52-64, https://stm1.bookpi.org/index.php/erms-v4/article/view/1265.