Sutharat Sirot และ Thasinee Charoentitirat. (2021) Oldest Fusulinid of Khao Khad Formation, Saraburi Province. <i>Bulletin of Earth Sciences of Thailand (BEST)</i>, <i>13</i>(1), 39-46.Sutharat Sirot และ Thasinee Charoentitirat. "Oldest Fusulinid of Khao Khad Formation, Saraburi Province". Bulletin of Earth Sciences of Thailand (BEST) 13 (2021):39-46.Sutharat Sirot และ Thasinee Charoentitirat. Oldest Fusulinid of Khao Khad Formation, Saraburi Province. Department of Geology, Chulalongkorn University:ม.ป.ท. 2021.