arXiv · 1104.1989
We review the results obtained in the last four decades which demonstrate the Efimov nature of the $^4$He three-atomic system.
Elena A. Kolganova, Alexander K. Motovilov, Werner Sandhas. 2011-04-11. The ^4He trimer as an Efimov system. https://doi.org/10.1007/s00601-011-0233-x
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