@article{Himmel:2017,
  author  = "M. Himmel",
  title   = "Complementary results to Heuver's characterization of logarithmic functions",
  journal = "Annales Mathematicae Silesianae",
  volume  = "Vol. 31",
  number  = "iss. 1",
  pages   = "99--106",
  year    = "2017",
}