Thongkham Souvanhnalath และ Pinyo Meechumna. (2015) Impurity removal from tin concentrate of Lao-Korea tin mine, Khammuan province, Lao PDR. Chulalongkorn University:ม.ป.ท.Thongkham Souvanhnalath และ Pinyo Meechumna. 2015. Impurity removal from tin concentrate of Lao-Korea tin mine, Khammuan province, Lao PDR. ม.ป.ท.:Chulalongkorn University;Thongkham Souvanhnalath และ Pinyo Meechumna. Impurity removal from tin concentrate of Lao-Korea tin mine, Khammuan province, Lao PDR. ม.ป.ท.:Chulalongkorn University, 2015. Print.