@unpublished{PikovskijZaksFeudeletal.1995,
  author    = {Pikovskij, Arkadij and Zaks, Michael A. and Feudel, Ulrike and Kurths, J{\"u}rgen},
  title     = {Singular continuous spectra in dissipative dynamics},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13787},
  year      = {1995},
  abstract  = {We demonstrate the occurrence of regimes with singular continuous (fractal) Fourier spectra in autonomous dissipative dynamical systems. The particular example in an ODE system at the accumulation points of bifurcation sequences associated to the creation of complicated homoclinic orbits. Two different machanisms responsible for the appearance of such spectra are proposed. In the first case when the geometry of the attractor is symbolically represented by the Thue-Morse sequence, both the continuous-time process and its descrete Poincar{\´e} map have singular power spectra. The other mechanism owes to the logarithmic divergence of the first return times near the saddle point; here the Poincar{\´e} map possesses the discrete spectrum, while the continuous-time process displays the singular one. A method is presented for computing the multifractal characteristics of the singular continuous spectra with the help of the usual Fourier analysis technique.},
  language  = {en}
}
@unpublished{PikovskijFeudel1994,
  author    = {Pikovskij, Arkadij and Feudel, Ulrike},
  title     = {Characterizing strange nonchaotic attractors},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-13405},
  year      = {1994},
  abstract  = {Strange nonchaotic attractors typically appear in quasiperiodically driven nonlinear systems. Two methods of their characterization are proposed. The first one is based on the bifurcation analysis of the systems, resulting from periodic approximations of the quasiperiodic forcing. Secondly, we propose th characterize their strangeness by calculating a phase sensitivity exponent, that measures the sensitivity with respect to changes of the phase of the external force. It is shown, that phase sensitivity appears if there is a non-zero probability for positive local Lyapunov exponents to occur.},
  language  = {en}
}
@article{StarkFeudelGlendinningetal.2002,
  author    = {Stark, J. and Feudel, Ulrike and Glendinning, P. A. and Pikovskij, Arkadij},
  title     = {Rotation numbers for quasi-periodically forced monotone circle maps},
  issn      = {1468-9367},
  year      = {2002},
  language  = {en}
}
@article{GlendinningFeudelPikovskijetal.2000,
  author    = {Glendinning, P. A. and Feudel, Ulrike and Pikovskij, Arkadij and Stark, J.},
  title     = {The structure of mode-locking regions in quasi-periodically forced circle maps},
  year      = {2000},
  language  = {en}
}
@article{KuznetsovFeudelPikovskij1998,
  author    = {Kuznetsov, Sergey P. and Feudel, Ulrike and Pikovskij, Arkadij},
  title     = {Renormalization group for scaling at the torus-doubling terminal point},
  year      = {1998},
  abstract  = {The quasiperiodically forced logistic map is analyzed at the terminal point of the torus-doubling bifurcation curve, where the dynamical regimes of torus, doubled torus, strange nonchaotic attractor, and chaos meet. Using the renormalization group approach we reveal scaling properties both for the critical attractor and for the parameter plane topography near the critical point.},
  language  = {en}
}
@misc{PikovskijFeudel1997,
  author    = {Pikovskij, Arkadij and Feudel, Ulrike},
  title     = {Comment on "Strange nonchaotic attractors in autonomous and periodically driven systems"},
  year      = {1997},
  abstract  = {The problem of the existence of strange nonchaotic attractors (SNA's) in autonomous systems is discussed. It is demonstrated that the recently reported example of a SNA in an autonomous system [V. S. Anishchenko et al., Phys. Rev. E 54, 3231 (1996)] is in fact a chaotic attractor with positive largest Lyapunov exponent.},
  language  = {en}
}
@article{WittFeudelPikovskij1997,
  author    = {Witt, Annette and Feudel, Ulrike and Pikovskij, Arkadij},
  title     = {Birth of strange nonchaotic attractors due to interior crisis},
  year      = {1997},
  language  = {en}
}
@article{KuznetsovPikovskijBezruckoetal.1997,
  author    = {Kuznetsov, Sergey P. and Pikovskij, Arkadij and Bezrucko, B. P. and Seleznev, E. P. and Feudel, Ulrike},
  title     = {O dinamike nelinejnych sistem po vne¬nim kvaziperiodi\Seskim vozdejstviem vblizi to\Ski okon\Sanija linii bifurkatcii udvoenija tora},
  year      = {1997},
  language  = {de}
}