Andreja Stojic participated the 4th International Conference on Proton Transfer Mass Spectrometry and its Applications and a training course Hands on PTR-MS in Obergurgl, Austria. He presented two posters: 'Assessment of ambient VOCs levels in Belgrade semi-urban area' and 'In vitro selection of nepetalactone-rich genotypes of Nepeta rtanjensis by using HPLC and PTR-MS, 17-19ht February 2009.