The effect of Acu-TENS on FEV1, six minute walk distance and dyspnoea in patients with chronic obstructive pulmonary disease: a randomised trial (B. M. Vyas, S. Shah, H. Tiwari, & A. Singh , Trans.). (2013). International Journal of Biomedical and Advance Research, 4(7), 448-454. https://doi.org/10.7439/ijbar.v4i7.392