Ngampong Kongkathip. 1998. Synthesis of betamethasone from steroids extracted from Agave sisalana. Bangkok:Kasetsart University;
Ngampong Kongkathip. (1998) Synthesis of betamethasone from steroids extracted from Agave sisalana (รายงานผลงานวิจัย). Kasetsart University:Bangkok.
Ngampong Kongkathip. Synthesis of betamethasone from steroids extracted from Agave sisalana. Bangkok:Kasetsart University, 1998.
Ngampong Kongkathip. (1998) Synthesis of betamethasone from steroids extracted from Agave sisalana (รายงานผลงานวิจัย). Kasetsart University:Bangkok.