Makomaski, G., et al. “The Use of Waste poly(ethylene Terephthalate) and Phenol-Formaldehyde Resin for the Preparation of Activated Carbons”. Polimery, vol. 57, no. 9, Sept. 2012, pp. 635-9, https://ichp.vot.pl/index.php/p/article/view/860.