[1]
O. P. Lelyakov, A. S. Karpenko, and R.-D. O. Babadzhan, “Dynamics of a Non-Rotating Test Null String in the Gravitational Field of a Closed ‘Thick’ Null String Radially Expanding or Collapsing in the Plane z = 0”, Ukr. J. Phys., vol. 59, no. 11, p. 1114, Oct. 2018.