Nipon Wiangwalai. 2004. A study of Pong-Lang ensemble in the secondary schools in Kalasin province, Thailand : school cluster 1. Field of Study Music, Mahidol University;
Nipon Wiangwalai. (2004) A study of Pong-Lang ensemble in the secondary schools in Kalasin province, Thailand : school cluster 1 . Mahidol University/Bangkok.
Nipon Wiangwalai. A study of Pong-Lang ensemble in the secondary schools in Kalasin province, Thailand : school cluster 1. . Bangkok:Mahidol University, 2004.
Nipon Wiangwalai. (2004) A study of Pong-Lang ensemble in the secondary schools in Kalasin province, Thailand : school cluster 1 . Mahidol University/Bangkok.