Nitirat Maleewat และ Sudawadee Chanpiwat. (2011) Increasing customer satisfaction through English language trianing program for housekeeping and security department : case study at Sofitel Bangkok Silom. Silpakorn University:ม.ป.ท.Nitirat Maleewat และ Sudawadee Chanpiwat. 2011. Increasing customer satisfaction through English language trianing program for housekeeping and security department : case study at Sofitel Bangkok Silom. ม.ป.ท.:Silpakorn University;Nitirat Maleewat และ Sudawadee Chanpiwat. Increasing customer satisfaction through English language trianing program for housekeeping and security department : case study at Sofitel Bangkok Silom. ม.ป.ท.:Silpakorn University, 2011. Print.