Berkout, V. D., & Doroshenko, V. M. (2006). Improving the Quality of the Ion Beam Exiting a Quadrupole Ion Guide. Journal of the American Society for Mass Spectrometry, 17(3), 335-340. https://doi.org/10.1016/j.jasms.2005.12.002

Berkout, Vadym D., and Vladimir M. Doroshenko. "Improving the Quality of the Ion Beam Exiting a Quadrupole Ion Guide." Journal of the American Society for Mass Spectrometry 17, no. 3 (2006): 335-340. https://doi.org/10.1016/j.jasms.2005.12.002.

Berkout, Vadym D., and Vladimir M. Doroshenko. "Improving the Quality of the Ion Beam Exiting a Quadrupole Ion Guide." Journal of the American Society for Mass Spectrometry, vol. 17, no. 3, 2006, pp. 335-340, https://doi.org/10.1016/j.jasms.2005.12.002.