Chaiyaphorn Pongsak. (1999) Problems in needs of police cadet on investigation training in Metropolitan Police Station. Mahidol University,:ม.ป.ท.Chaiyaphorn Pongsak. 1999. Problems in needs of police cadet on investigation training in Metropolitan Police Station. ม.ป.ท.:Mahidol University,;Chaiyaphorn Pongsak. Problems in needs of police cadet on investigation training in Metropolitan Police Station. ม.ป.ท.:Mahidol University, 1999. Print.