1. . US Patent 2939952, 1960.
2. . Vacuum Physics and Technologies and Its Applications in Electronic Components, part I, chap. 4. National Defense Industry Press: Beijing, 1982.
3. European Patent EPO202943A2, 1986.
4. , , . In Practical Aspects of Ion Trap Mass Spectrometry, vol. II, (eds). 1995; chap. 1.
5. . In Practical Aspects of Ion Trap Mass Spectrometry, vol. I, (eds). 1995, chap. 2.