@incollection{AbeleKleefeld2020,
  author    = {Daniel Abele and Andreas Kleefeld},
  title     = {New Numerical Results for the Optimization of Neumann Eigenvalues},
  booktitle = {Computational and Analytic Methods in Science and Engineering},
  editor    = {Christian Constanda},
  isbn      = {978-3-030-48185-8 (Print)},
  doi       = {10.1007/978-3-030-48186-5_1},
  year      = {2020},
}