Sampe, Jahariah, et al. “ULTRA LOW POWER HYBRID MICRO ENERGY HARVESTER USING RF, THERMAL AND VIBRATION FOR BIOMEDICAL DEVICES”. International Journal of Pharmacy and Pharmaceutical Sciences, vol. 8, no. 2, Sept. 2016, pp. 18-21, doi:10.22159/ijpps.2016v8s2.15213.