Zavilopulo, A., and O. Shpenik. “Electron-Impact Mass Spectrometry of PTCDA Molecules in the Gas Phase”. Ukrainian Journal of Physics 64, no. 1 (January 30, 2019): 3. Accessed July 24, 2024. https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2018127.