@article{FredebeulKreinVogel2006,
  author    = {Fredebeul-Krein, Markus and Vogel, Erika},
  title     = {Underground Storage Facilities in the German natural gas market: A need for access regulation to ensure competition?},
  series = {Zeitschrift f{\"u}r Energiewirtschaft. 30 (2006), H. 4},
  journal   = {Zeitschrift f{\"u}r Energiewirtschaft. 30 (2006), H. 4},
  isbn      = {0343-5377},
  pages     = {257 -- 270},
  year      = {2006},
  language  = {en}
}
@article{KaltschmittThraenFredebeulKreinetal.2006,
  author    = {Kaltschmitt, Martin and Thr{\"a}n, Daniela and Fredebeul-Krein, Markus and Vogel, Erika and Kalitzky, Thomas and Ehrhart, Karl Martin and Hoppe, Christian and Seifert, Stefan and Sijm, Jos and B{\"o}hringer, Christoph and Hoffmann, Tim and Moslener, Ulf and Sturm, Bodo and Diekmann, Jochen and Schleich, Joachim},
  title     = {CO2-Emissionshandel},
  series = {Zeitschrift f{\"u}r Energiewirtschaft},
  volume    = {Vol. 30},
  journal   = {Zeitschrift f{\"u}r Energiewirtschaft},
  number    = {Iss. 4},
  issn      = {0343-5377 (Print) 1866-2765 (Online)},
  pages     = {271 -- 314},
  year      = {2006},
  language  = {de}
}