X-ray spectroscopy study on Thai amulet of Phra Kru NaduneKrit Won-in, Chatdanai Boonruang, Udomrat Tippawan, Chome Thongleurm and Pisutti DararutanaEPJ Web Conf., 261 (2022) 04003DOI: https://doi.org/10.1051/epjconf/202226104003