@article{HelsperFissan1981,
  author    = {Helsper, Christoph and Fißan, H. J.},
  title     = {Response Characteristic of a Polytec HC-15 Optical Particle Counter},
  series = {Aerosols in science, medicine and technology : Physical and chemical properties of aerosols : Association for Aerosol Research: annual conference. 1980 : Gesellschaft f{\"u}r Aerosolforschung: annual conference. 1980 : Aerosols in science, medicine and technology : Physical and chemical properties of aerosols : Associa-tion for Aerosol Research: annual conference. 1980 : Gesellschaft f{\"u}r Aerosolforschung: annual conference. 1980 : Schmallenberg, 22.10.80 - 24.10.80},
  journal   = {Aerosols in science, medicine and technology : Physical and chemical properties of aerosols : Association for Aerosol Research: annual conference. 1980 : Gesellschaft f{\"u}r Aerosolforschung: annual conference. 1980 : Aerosols in science, medicine and technology : Physical and chemical properties of aerosols : Associa-tion for Aerosol Research: annual conference. 1980 : Gesellschaft f{\"u}r Aerosolforschung: annual conference. 1980 : Schmallenberg, 22.10.80 - 24.10.80},
  publisher = {Pergamon Pr.},
  address   = {Oxford},
  pages     = {287 -- 292},
  year      = {1981},
  language  = {en}
}
@article{HelsperFissanKapadietal.1982,
  author    = {Helsper, Christoph and Fißan, H. J. and Kapadi, A. and Liu, B. Y. H.},
  title     = {Data Inversion by Simplex Minimization for the Electrical Aerosol Analyzer},
  series = {Aerosol Science and Technology. 1 (1982), H. 1982},
  journal   = {Aerosol Science and Technology. 1 (1982), H. 1982},
  isbn      = {0278-6826},
  pages     = {136 -- 146},
  year      = {1982},
  language  = {en}
}
@article{Mackenstein1991,
  author    = {Mackenstein, Hans},
  title     = {The role of Germany, Japan and the United States on the ECU-bond markets / Hans Wilhelm Mackenstein},
  series = {De pecunia. 3 (1991), H. 1},
  journal   = {De pecunia. 3 (1991), H. 1},
  isbn      = {1015-6283},
  pages     = {113 -- 150},
  year      = {1991},
  language  = {en}
}
@article{MackensteinJeffery1999,
  author    = {Mackenstein, Hans and Jeffery, Charlie},
  title     = {Financial equalization in the 1990s : on the road back to Karlsruhe / Hans Mackenstein and Charlie Jeffery},
  series = {Recasting German federalism : the legacies of unification},
  journal   = {Recasting German federalism : the legacies of unification},
  publisher = {Pinter},
  address   = {London},
  isbn      = {1-85567-579-x},
  pages     = {155 -- 176},
  year      = {1999},
  language  = {en}
}
@article{Mackenstein2000,
  author    = {Mackenstein, Hans},
  title     = {Books Reviewed - European Democratization since 1800 edited by J. Garrard, V. Tolz and R. White},
  series = {Democratization. 7 (2000), H. 4},
  journal   = {Democratization. 7 (2000), H. 4},
  isbn      = {1351-0347},
  pages     = {219 -- 219},
  year      = {2000},
  language  = {en}
}
@article{Mackenstein1999,
  author    = {Mackenstein, Hans},
  title     = {Book Reviews - Cowie, Harry, Private Partnership and Public Networks in Europe},
  series = {Regional and federal studies. 9 (1999), H. 2},
  journal   = {Regional and federal studies. 9 (1999), H. 2},
  isbn      = {1359-7566},
  pages     = {111 -- 111},
  year      = {1999},
  language  = {en}
}
@article{HelsperMoelter1989,
  author    = {Helsper, Christoph and M{\"o}lter, L.},
  title     = {Erzeugung von Pr{\"u}faerosolen f{\"u}r die Kalibrierung von optischen Partikelmeßverfahren nach VDI 3491},
  series = {Technisches Messen. 56 (1989)},
  journal   = {Technisches Messen. 56 (1989)},
  isbn      = {0171-8096},
  pages     = {229 -- 234},
  year      = {1989},
  language  = {en}
}
@article{HelsperMoelterKaminski1989,
  author    = {Helsper, Christoph and M{\"o}lter, W. and Kaminski, S.},
  title     = {Fast and Automated Testing of Different Air Filter Media / M{\"o}lter, W. ; Helsper, C. ; Kaminski, S.},
  series = {1. Europ{\"a}isches Symposium Partikelabscheidung aus Gasen : [PARTEC, N{\"u}rnberg, West Germany, 19. - 21. April 1989 ; preprints] = 1. European Symposium Separation of Particles from Gases / [Organisation und Durchf{\"u}hrung: N{\"u}rnbergMesse]. Hrsg. von: Friedrich L{\"o}ffler},
  journal   = {1. Europ{\"a}isches Symposium Partikelabscheidung aus Gasen : [PARTEC, N{\"u}rnberg, West Germany, 19. - 21. April 1989 ; preprints] = 1. European Symposium Separation of Particles from Gases / [Organisation und Durchf{\"u}hrung: N{\"u}rnbergMesse]. Hrsg. von: Friedrich L{\"o}ffler},
  publisher = {N{\"u}rnbergMesse},
  address   = {N{\"u}rnberg},
  pages     = {441 -- 457},
  year      = {1989},
  language  = {en}
}
@article{HelsperMoelterKaminski1989,
  author    = {Helsper, Christoph and M{\"o}lter, W. and Kaminski, S.},
  title     = {Fast and Automated Testing of Different Air Filter Media / M{\"o}lter, W. ; Helsper, C. ; Kaminski, S.},
  series = {Proceedings of the Filtech Conference, Karlsruhe 1989, Vol. 1},
  journal   = {Proceedings of the Filtech Conference, Karlsruhe 1989, Vol. 1},
  publisher = {Filtration Society},
  address   = {Oadby},
  pages     = {125 -- 136},
  year      = {1989},
  language  = {en}
}
@article{HelsperMoelter1991,
  author    = {Helsper, Christoph and M{\"o}lter, W.},
  title     = {Characteristics of a Nebulizer with Cyclone Preseparator / M{\"o}lter, W. ; Helsper, C.},
  series = {Aerosols, their generation, behaviour and applications. Annual Conference of the Aerosol Society / Aerosol Society (UK) ; 5.},
  journal   = {Aerosols, their generation, behaviour and applications. Annual Conference of the Aerosol Society / Aerosol Society (UK) ; 5.},
  address   = {Loughborough},
  pages     = {89 -- 94},
  year      = {1991},
  language  = {en}
}