Agano, Toshitaka, et al. “Effect of Light Pulse Width on Frequency Characteristics of Photoacoustic Signal – an Experimental Study Using a Pulse-Width Tunable LED-Based Photoacoustic Imaging System”. International Journal of Engineering & Technology, vol. 7, no. 4, Dec. 2018, pp. 4300-3, https://doi.org/10.14419/ijet.v7i4.19907.