Structure of the excitation spectrum of liquid 4He.

@article{Blagoveshchenskii1994StructureOT,
  title={Structure of the excitation spectrum of liquid 4He.},
  author={Blagoveshchenskii and Bogoyavlenskii and Karnatsevich and V G Kozlov and Kolobrodov and Priezzhev and Puchkov and Skomorokhov and Yarunin},
  journal={Physical review. B, Condensed matter},
  year={1994},
  volume={50 22},
  pages={16550-16565}
}