@article{HagemannGeittnerLydtinetal.1988,
  author    = {Hagemann, Hans-J{\"u}rgen and Geittner, P. and Lydtin, H. and Warnier, J.},
  title     = {Hybrid technology for large SM-fiber preforms. Geittner, P.; Hagemann, H. J.; Lydtin, H.; Warnier, J.},
  series = {Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 6 (1988), H. 10},
  journal   = {Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 6 (1988), H. 10},
  isbn      = {0733-8724},
  pages     = {1451 -- 1454},
  year      = {1988},
  language  = {en}
}
@article{HagemannUngelenkWiechert1990,
  author    = {Hagemann, Hans-J{\"u}rgen and Ungelenk, J. and Wiechert, D. U.},
  title     = {Optical time domain reflectometry (OTDR) of diameter modulations in single-mode fibers. Hagemann, H. J.; Ungelenk, J.; Wiechert, D. U.},
  series = {Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 8 (1990), H. 11},
  journal   = {Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 8 (1990), H. 11},
  isbn      = {0733-8724},
  pages     = {1641 -- 1645},
  year      = {1990},
  language  = {en}
}
@article{HagemannGeittnerWarnieretal.1986,
  author    = {Hagemann, Hans-J{\"u}rgen and Geittner, P. and Warnier, J. and Wilson, H.},
  title     = {PCVD at high deposition rates. Geittner, P.; Hagemann, H. J.; Warnier, J.; Wilson, H.},
  series = {Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 4 (1986), H. 7},
  journal   = {Journal of Lightwave Technology (J-LT) / Institute of Electrical and Electronics Engineers (IEEE). 4 (1986), H. 7},
  isbn      = {0733-8724},
  pages     = {818 -- 822},
  year      = {1986},
  language  = {en}
}
@article{HagemannStumpeWagneretal.1985,
  author    = {Hagemann, Hans-J{\"u}rgen and Stumpe, R. and Wagner, D. and B{\"a}uerle, D.},
  title     = {The influence of contact effects on the dielectric behavior of diffuse phase transitions. Stumpe, R.; Wagner, D.; B{\"a}uerle, D.; Hagemann, H. J.},
  series = {Ferroelectrics : the international journal devoted to the theoretical, experimental, and applied aspects of ferroelectrics and related materials / Letters section. 4 (1985)},
  journal   = {Ferroelectrics : the international journal devoted to the theoretical, experimental, and applied aspects of ferroelectrics and related materials / Letters section. 4 (1985)},
  isbn      = {0731-5171},
  pages     = {143 -- 147},
  year      = {1985},
  language  = {en}
}
@article{HagemannGeittnerWarnieretal.1985,
  author    = {Hagemann, Hans-J{\"u}rgen and Geittner, P. and Warnier, J. and Weling, F.},
  title     = {Reduction of geometric taper losses in the PCVD process. Geittner, P.; Hagemann, H. J.; Warnier, J.; Weling, F.; Wilson, H.},
  series = {Electronics letters : an intern. publication / The Institution of Electrical Engineers. 21 (1985), H. 13},
  journal   = {Electronics letters : an intern. publication / The Institution of Electrical Engineers. 21 (1985), H. 13},
  isbn      = {0013-5194},
  pages     = {870 -- 871},
  year      = {1985},
  language  = {en}
}
@article{HagemannGeittnerLeers1989,
  author    = {Hagemann, Hans-J{\"u}rgen and Geittner, P. and Leers, D.},
  title     = {Intrinsic scattering and absorption losses of Ge- and F-doped optical fibres prepared by PCVD. Geittner, P.; Hagemann, H. J. ; Leers, D.},
  series = {Electronics letters : an intern. publication / The Institution of Electrical Engineers. 25 (1989), H. 7},
  journal   = {Electronics letters : an intern. publication / The Institution of Electrical Engineers. 25 (1989), H. 7},
  isbn      = {0013-5194},
  pages     = {436 -- 437},
  year      = {1989},
  language  = {en}
}
@article{HagemannHennings1981,
  author    = {Hagemann, Hans-J{\"u}rgen and Hennings, D.},
  title     = {Reversible Weight change of acceptor-doped BaTiO3. Hagemann, H. J.; Hennings, D.},
  series = {Journal of the American Ceramic Society. 64 (1981)},
  journal   = {Journal of the American Ceramic Society. 64 (1981)},
  isbn      = {0002-7820},
  pages     = {590 -- 594},
  year      = {1981},
  language  = {en}
}
@article{HagemannHenningsWernicke1984,
  author    = {Hagemann, Hans-J{\"u}rgen and Hennings, D. and Wernicke, R.},
  title     = {Ceramic multilayer capacitors. Hagemann, H. J.; Hennings, D.; Wernicke, R.},
  series = {Philips' technical review / Philips' Gloeilampenfabrieken. Philips' Gloeilampenfabrieken <Eindhoven>. 41 (1984)},
  journal   = {Philips' technical review / Philips' Gloeilampenfabrieken. Philips' Gloeilampenfabrieken <Eindhoven>. 41 (1984)},
  isbn      = {0031-7926},
  pages     = {89 -- 98},
  year      = {1984},
  language  = {en}
}
@article{HagemannHeroGonser1980,
  author    = {Hagemann, Hans-J{\"u}rgen and Hero, A. and Gonser, U.},
  title     = {The valence change of Fe in BaTiO3 studied by M{\"o}ßbauer effect and gravimetry. Hagemann, H. J.; Hero, A.; Gonser, U.},
  series = {Physica Status Solidi (A) - Applied Research. 61 (1980)},
  journal   = {Physica Status Solidi (A) - Applied Research. 61 (1980)},
  isbn      = {0031-8965},
  pages     = {63 -- 72},
  year      = {1980},
  language  = {en}
}
@article{HagemannIhrig1979,
  author    = {Hagemann, Hans-J{\"u}rgen and Ihrig, H.},
  title     = {Valence change and phase stability of 3d-doped BaTiO3 annealed in oxygen and hydrogen. Hagemann, H. J.; Ihrig, H.},
  series = {Physical Review B.. 20 (1979), H. 9},
  journal   = {Physical Review B.. 20 (1979), H. 9},
  isbn      = {1095-3795},
  pages     = {3871 -- 3878},
  year      = {1979},
  language  = {en}
}