Investigation on the Deterioration Mechanism of Tuff Stones Used for the Exteriors at the Former Koshien HotelKoki Yamada, Chiemi Iba, Tomoko Uno, Kazuma Fukui and Daisuke OguraE3S Web Conf., 172 (2020) 20008DOI: https://doi.org/10.1051/e3sconf/202017220008