Prapanpong Pongsriiam. (2015) Functions which preserve various types of distances. Silpakorn University:ม.ป.ท.Prapanpong Pongsriiam. 2015. Functions which preserve various types of distances. ม.ป.ท.:Silpakorn University;Prapanpong Pongsriiam. Functions which preserve various types of distances. ม.ป.ท.:Silpakorn University, 2015. Print.