“Utilising Lapindo Sidoarjo Mud and Mount Merapi Yogyakarta Ash As Alternative Materials for Earthenware and Stoneware Manufacture”. Wacana Seni Journal of Arts Discourse, vol. 18, Nov. 2019, pp. 125–142, https://ejournal.usm.my/wacanaseni/article/view/ws-vol18-2019-6.