Kolganova, E. A.; Motovilov, A. K.; Sandhas, W. (4 May 2011). "The 4He Trimer as an Efimov System". Few-Body Systems51 (2–4): 249–257. doi:10.1007/s00601-011-0233-x. Bibcode: 2011FBS....51..249K.
Kunitski, M.; Zeller, S.; Voigtsberger, J.; Kalinin, A.; Schmidt, L. P. H.; Schoffler, M.; Czasch, A.; Schollkopf, W. et al. (30 April 2015). "Observation of the Efimov state of the helium trimer". Science348 (6234): 551–555. doi:10.1126/science.aaa5601. பப்மெட்:25931554. Bibcode: 2015Sci...348..551K.
Kolganova, E. A.; Motovilov, A. K.; Sandhas, W. (4 May 2011). "The 4He Trimer as an Efimov System". Few-Body Systems51 (2–4): 249–257. doi:10.1007/s00601-011-0233-x. Bibcode: 2011FBS....51..249K.
Kunitski, M.; Zeller, S.; Voigtsberger, J.; Kalinin, A.; Schmidt, L. P. H.; Schoffler, M.; Czasch, A.; Schollkopf, W. et al. (30 April 2015). "Observation of the Efimov state of the helium trimer". Science348 (6234): 551–555. doi:10.1126/science.aaa5601. பப்மெட்:25931554. Bibcode: 2015Sci...348..551K.
Kunitski, M.; Zeller, S.; Voigtsberger, J.; Kalinin, A.; Schmidt, L. P. H.; Schoffler, M.; Czasch, A.; Schollkopf, W. et al. (30 April 2015). "Observation of the Efimov state of the helium trimer". Science348 (6234): 551–555. doi:10.1126/science.aaa5601. பப்மெட்:25931554. Bibcode: 2015Sci...348..551K.