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								[1]
								Poncet A. Ion Trapping and Cleaning, Proc. 1989 CERN Acc.School, CERN 90–14(1990) [2] Courant E D, Snyder H. Ann. Phys., 1958, 3:1 
Poncet A. Ion Trapping and Cleaning, Proc. 1989 CERN Acc.School, CERN 90–14(1990) [2] Courant E D, Snyder H. Ann. Phys., 1958, 3:1