@book{AltSchumny1983,
  author    = {Alt, Helmut and Schumny, Harald},
  title     = {Schreiben, Zeichnen, Tabellieren : (TI-59, HP-41 C) (Vieweg-Programmbibliothek Taschenrechner ; 4) / Helmut Alt ; Harald Schumny [Hrsg.]},
  publisher = {Vieweg + Teubner},
  address   = {Wiesbaden},
  isbn      = {3-528-04233-8},
  pages     = {77 S.},
  year      = {1983},
  language  = {de}
}
@book{AltSchumny1983,
  author    = {Alt, Helmut and Schumny, Harald},
  title     = {Taschenrechnerarithmetik mit erh{\"o}hter Genauigkeit (TI-59/HP-41C) (Vieweg-Programmbibliothek Taschenrechner ; 2) / Helmut Alt ; Harald Schumny [Hrsg.]},
  publisher = {Vieweg + Teubner},
  address   = {Wiesbaden},
  isbn      = {3-528-04229-X ; 978-3-322-91099-8 ; 978-3-528-04229-5},
  pages     = {III, 58 S.},
  year      = {1983},
  language  = {de}
}
@book{AltSchumny1982,
  author    = {Alt, Helmut and Schumny, Harald},
  title     = {Programmierung mathematischer Algorithmen (Vieweg-Programmbibliothek Taschenrechner ; 1) / Helmut Alt ; Harald Schumny [Hrsg.]},
  publisher = {Vieweg + Teubner},
  address   = {Wiesbaden},
  isbn      = {3-528-04211-7},
  pages     = {92 S.},
  year      = {1982},
  language  = {de}
}
@book{AltensenAltSchumny1983,
  author    = {Altensen, Frank and Alt, Helmut and Schumny, Harald},
  title     = {Kryptologie (HP-41 C/CV) : Chiffrierung, Textverschl{\"u}sselung, Datenschutz, Morsealphabet (Vieweg-Programmbibliothek Taschenrechner ; 7) / Helmut Alt ; Harald Schumny [Hrsg.]},
  publisher = {Vieweg + Teubner},
  address   = {Wiesbaden},
  isbn      = {3-528-04256-7},
  pages     = {V, 92 S.},
  year      = {1983},
  language  = {de}
}
@book{MaiSchumnyAlt1984,
  author    = {Mai, Herbert and Schumny, Harald and Alt, Helmut},
  title     = {Lineares Optimieren : Maximierung - Minimierung (Vieweg Programmbibliothek Mikrocomputer ; 14) / Helmut Alt ; Harald Schumny [Hrsg.]},
  publisher = {Vieweg + Teubner},
  address   = {Wiesbaden},
  isbn      = {978-3-663-14049-8 ; 978-3-528-04312-4},
  pages     = {VIII, 100 S.},
  year      = {1984},
  language  = {de}
}