@article{Hassler2008,
  author    = {Haßler, Gerda},
  title     = {Indicative verb forms as means of expressing modality in romance languages},
  isbn      = {978-1-443-84059-0},
  year      = {2008},
  language  = {en}
}
@article{Hassler2008,
  author    = {Haßler, Gerda},
  title     = {Introduction},
  isbn      = {978-90-272-4606-6},
  year      = {2008},
  language  = {en}
}