@book{Nothdurft2014,
  author    = {Werner Nothdurft},
  title     = {\"... {\"a}h folgendes Problem {\"a}h...\"},
  publisher = {Narr},
  address   = {T{\"u}bingen},
  isbn      = {3-87808-657-1},
  url       = {https://nbn-resolving.org/urn:nbn:de:bsz:mh39-20989},
  pages     = {234 S.},
  year      = {2014},
  language  = {de}
}