@inproceedings{Wirsching1997,
  author    = {{Günther J. Wirsching}},
  title     = {{$3n+1$ Predecessor Densities and Uniform Distribution in $\mathbb{Z}_3^\ast$}},
  booktitle = {{Proc. Conference on Elementary and Analytic Number Theory}},
  year      = {{1996}},
  pages     = {{230-240}},
  note      = {{Zbl. 883.11010}},
}