@phdthesis{Goebels2004,
  author      = {Thomas Goebels},
  title       = {Die Bewertung von Umweltmanagementsystemen},
  type        = {doctoralthesis},
  school      = {Universit{\"a}t Trier},
  doi       = {10.25353/ubtr-xxxx-48e1-db2d},
  year        = {2004},
}