@book{KrupchykTarkhanovTuomela2005,
  author    = {Krupchyk, K. and Tarkhanov, Nikolai Nikolaevich and Tuomela, J.},
  title     = {Generalised elliptic boundary problems},
  series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell},
  journal   = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell},
  publisher = {Univ.},
  address   = {Potsdam},
  issn      = {1437-739X},
  pages     = {27 S.},
  year      = {2005},
  language  = {en}
}
@book{KrupchykTarkhanovTuomela2006,
  author    = {Krupchyk, K. and Tarkhanov, Nikolai Nikolaevich and Tuomela, J.},
  title     = {Elliptic quasicomplexes in boutet de monvel algebra},
  series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell},
  journal   = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell},
  publisher = {Univ.},
  address   = {Potsdam},
  issn      = {1437-739X},
  pages     = {24 S.},
  year      = {2006},
  language  = {en}
}