Berezhiani, Lasha Max Planck Institute for Physics, Max Planck Society and Cooperation Partners;
https://publications.mppmu.mpg.de/2020/MPP-2020-362/FullText.0-S0370269320302550-main.pdf (Any fulltext)
Berezhiani, L. (2020). On Effective Theory of Superfluid Phonons. Physics Letters B, 805, 135451. doi:10.1016/j.physletb.2020.135451.