@article{itb2860,
  author = {Gessler, Michael and Siemer, Christine},
  title = {Umbrella review: Methodological review of reviews published in peer-reviewed journals with a substantial focus on vocational education and training research},
  year = {2020},
  journal = {International Journal for Research in Vocational Education and Training},
  volume = {7},
  number = {1},
  pages = {91–125},
  doi = {10.13152/IJRVET.7.1.5},
  language = {de},
}