L. P. Kondaurova and V. A. Andryushchenko, Dynamics, properties and spectrum of reconnecting vortex loops in superfluid helium (Review Article), Low Temp. Phys. 47, (2021) [Fiz. Nizk. Temp. 47, 804-818, (2021)] DOI: https://doi.org/10.1063/10.0005797.