Rapid direct determination of pesticides and metabolites in environmental water samples at sub-μg/l level by on-line solid-phase extraction-liquid chromatography–electrospray tandem mass spectrometry
F. Hernández, J. V. Sancho, O. Pozo, A. Lara and E. Pitarch
Journal of Chromatography A
Volume 939, Issues 1-2, 21 December 2001, Pages 1-11
doi:10.1016/S0021-9673(01)01334-6   
  http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TG8-44MG2B5-1&_user=6771478&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=993362742&_rerunOrigin=scholar.google&_acct=C000070531&_version=1&_urlVersion=0&_userid=6771478&md5=20c4a982192c0d5588dad2e78320be8d