Rety Winonazada, Listiyawati Nugraha and S. Koesnaryo (2020) “Limestone Hardness Classification Based on Compressive Strength Value in Ponjong District, Semanu District, and Tanjungsari District, Gunung Kidul Regency, Yogyakarta”, ReTII, pp. 221-226. Available at: //journal.itny.ac.id/index.php/ReTII/article/view/2051 (Accessed: 24November2024).