@article{SavinSternin2005,
  author    = {Savin, Anton and Sternin, Boris},
  title     = {Boundary value problems on manifolds with fibered boundary},
  issn      = {0025-584X},
  year      = {2005},
  abstract  = {We define a class of boundary value problems on manifolds with fibered boundary. This class is in a certain sense a deformation between the classical boundary value problems and the Atiyah-Patodi-Singer problems in subspaces (it contains both as special cases). The boundary conditions in this theory are taken as elements of the C*-algebra generated by pseudodifferential operators and families of pseudodifferential operators in the fibers. We prove the Fredholm. property for elliptic boundary value problems and compute a topological obstruction (similar to Atiyah-Bott obstruction) to the existence of elliptic boundary conditions for a given elliptic operator. Geometric operators with trivial and nontrivial obstruction are given. (c) 2005 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim},
  language  = {en}
}
@book{SavinSternin2005,
  author    = {Savin, Anton and Sternin, Boris},
  title     = {Pseudodifferential subspaces and their applications in elliptic theory},
  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     = {46 S.},
  year      = {2005},
  language  = {en}
}
@unpublished{SavinSternin2005,
  author    = {Savin, Anton and Sternin, Boris},
  title     = {Pseudodifferential subspaces and their applications in elliptic theory},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-29937},
  year      = {2005},
  abstract  = {The aim of this paper is to explain the notion of subspace defined by means of pseudodifferential projection and give its applications in elliptic theory. Such subspaces are indispensable in the theory of well-posed boundary value problems for an arbitrary elliptic operator, including the Dirac operator, which has no classical boundary value problems. Pseudodifferential subspaces can be used to compute the fractional part of the spectral Atiyah-Patodi-Singer eta invariant, when it defines a homotopy invariant (Gilkey's problem). Finally, we explain how pseudodifferential subspaces can be used to give an analytic realization of the topological K-group with finite coefficients in terms of elliptic operators. It turns out that all three applications are based on a theory of elliptic operators on closed manifolds acting in subspaces.},
  language  = {en}
}