Pimkwan Chantaratepra และ Orawan Chailapakul. (2009) On-line solid phase extraction coupled with sequential injection system for determination of sulfonamides. Chulalongkorn University:ม.ป.ท.Pimkwan Chantaratepra และ Orawan Chailapakul. 2009. On-line solid phase extraction coupled with sequential injection system for determination of sulfonamides. ม.ป.ท.:Chulalongkorn University;Pimkwan Chantaratepra และ Orawan Chailapakul. On-line solid phase extraction coupled with sequential injection system for determination of sulfonamides. ม.ป.ท.:Chulalongkorn University, 2009. Print.