@conference {Vlcek_EBT_2009, title = {Study of the Welding Electron Gun Optical Properties for Work Piece Imaging}, booktitle = {Proceedings of the 9th International Conference on Electron Beam Technologies}, year = {2009}, pages = {70{\textendash}72}, publisher = {Bulgarian Academy of Sciencies}, organization = {Bulgarian Academy of Sciencies}, address = {Varna}, issn = {0861-4717}, author = {Ivan Vl{\v c}ek}, editor = {Georgy Mladenov} }