TD-GC-MS Analysis of Volatile Metabolites of Human Lung Cancer and Normal Cells In vitro Wojciech Filipiak, Andreas Sponring, Anna Filipiak, Clemens Ager, Jochen K. Schubert, Wolfram Miekisch, Anton Amann and Jakob Troppmair 2010 doi:10.1158/1055-9965.EPI-09-0162 pdf