J Ling; M D West; T Lafleur; C Charles; R W Boswell (2010). "Thrust measurements in a low-magnetic field high-density mode in the helicon double layer thruster". Journal of Physics D: Applied Physics. 43 (30). IOP Publishing. Bibcode:2010JPhD...43D5203L. doi:10.1088/0022-3727/43/30/305203.
J Ling; M D West; T Lafleur; C Charles; R W Boswell (2010). "Thrust measurements in a low-magnetic field high-density mode in the helicon double layer thruster". Journal of Physics D: Applied Physics. 43 (30). IOP Publishing. Bibcode:2010JPhD...43D5203L. doi:10.1088/0022-3727/43/30/305203.