@article{HelsperMoelterKaminski1992,
  author    = {Helsper, Christoph and M{\"o}lter, W. and Kaminski, S.},
  title     = {Fast, Automated Testing of Different Air Filter Media / M{\"o}lter, W. ; Helsper, C. ; Kaminski, S.},
  series = {Filtration and Separation. 29 (1992), H. 1},
  journal   = {Filtration and Separation. 29 (1992), H. 1},
  isbn      = {0015-1882},
  pages     = {45 -- 50},
  year      = {1992},
  language  = {en}
}
@article{Helsper1993,
  author    = {Helsper, Christoph},
  title     = {Integrit{\"a}tspr{\"u}fung an LF-Anlagen mit Hilfe von Pr{\"u}faerosolen},
  series = {Pharma-Technologie-Journal. 14 (1993), H. 2},
  journal   = {Pharma-Technologie-Journal. 14 (1993), H. 2},
  isbn      = {0931-9700},
  pages     = {36 -- 42},
  year      = {1993},
  language  = {de}
}
@article{HelsperDreilingHalleretal.1986,
  author    = {Helsper, Christoph and Dreiling, V. and Haller, P. and Kaminski, U.},
  title     = {Intercomparison of Eleven Condensation Nucleus Counters / Dreiling, V. ; Haller, P. ; Helsper, C.; Kaminski, U. ; Plomp, A. ; Raes, F. ; Roth, C. ; Schier, J. ; Sch{\"u}rmann, G.},
  series = {Journal of Aerosol Science. 17 (1986), H. 3},
  journal   = {Journal of Aerosol Science. 17 (1986), H. 3},
  isbn      = {0021-8502},
  pages     = {565 -- 570},
  year      = {1986},
  language  = {en}
}
@article{HelsperHornSchneideretal.2008,
  author    = {Helsper, Christoph and Horn, Hans-Georg and Schneider, Friedhelm and Wehner, Birgit},
  title     = {Intercomparison of five mobility size spectrometers for measuring atmospheric submicrometer aerosol particles / Helsper, Christoph ; Horn, Hans-Georg ; Schneider, Friedhelm ; Wehner, Birgit ; Wiedensohler, Alfred},
  series = {Gefahrstoffe, Reinhaltung der Luft. Air Quality Control. 68 (2008), H. 11-12},
  journal   = {Gefahrstoffe, Reinhaltung der Luft. Air Quality Control. 68 (2008), H. 11-12},
  isbn      = {0949-8036},
  pages     = {475 -- 481},
  year      = {2008},
  language  = {en}
}
@article{HelsperWiedensohlerLuetkemeieretal.1986,
  author    = {Helsper, Christoph and Wiedensohler, A. and L{\"u}tkemeier, E. and Feldpausch, M.},
  title     = {Investigation on the Bipolar Charge Distribution at Various Gas Conditions / Wiedensohler, A.; L{\"u}tkemeier, E.; Feldpausch, M. ; Helsper, C.},
  series = {Journal of Aerosol Science. 17 (1986), H. 3},
  journal   = {Journal of Aerosol Science. 17 (1986), H. 3},
  isbn      = {0021-8502},
  pages     = {413 -- 416},
  year      = {1986},
  language  = {en}
}
@article{HelsperMoelterLoeffleretal.1993,
  author    = {Helsper, Christoph and M{\"o}lter, W. and L{\"o}ffler, F. and Wadenpohl, C.},
  title     = {Investigations on a New Aerosol Generator for the Production of Carbon Aggregate Particles / Helsper, C. ; M{\"o}lter, W. ; L{\"o}ffler, F. ; Wadenpohl, C. ; Kaufmann, S. ; Wenninger, G.},
  series = {Atmospheric Environment. Part A. General Topics. 27 A (1993), H. 8},
  journal   = {Atmospheric Environment. Part A. General Topics. 27 A (1993), H. 8},
  isbn      = {1352-2310},
  pages     = {1271 -- 1275},
  year      = {1993},
  language  = {en}
}
@article{HelsperFissanKasper1984,
  author    = {Helsper, Christoph and Fißan, H. J. and Kasper, W.},
  title     = {Kalibrierung der Partikelgr{\"o}ßenbestimmung von optischen Partikelz{\"a}hlern / Fißan, H. J.; Helsper, C. ; Kasper, W.},
  series = {3. Europ{\"a}isches Symposion Partikelmeßtechnik : [PARTEC, eine Veranstaltung der Reihe Partikel-Technologie N{\"u}rnberg ; N{\"u}rnberg, 9. - 11. Mai 1984 ; preprints] = 3. European Symposium on Particle Characterization / Veranst.: GVC, Gesellschaft Verfahrenstechnik und Chemieingenieurwesen im Verein Deutscher Ingenieure (VDI). Red. Bearb.: Kurt Leschonski},
  journal   = {3. Europ{\"a}isches Symposion Partikelmeßtechnik : [PARTEC, eine Veranstaltung der Reihe Partikel-Technologie N{\"u}rnberg ; N{\"u}rnberg, 9. - 11. Mai 1984 ; preprints] = 3. European Symposium on Particle Characterization / Veranst.: GVC, Gesellschaft Verfahrenstechnik und Chemieingenieurwesen im Verein Deutscher Ingenieure (VDI). Red. Bearb.: Kurt Leschonski},
  publisher = {NMA N{\"u}rnberger Messe- und Ausstellungsges.},
  address   = {N{\"u}rnberg},
  pages     = {263 -- 274},
  year      = {1984},
  language  = {de}
}
@article{Helsper1988,
  author    = {Helsper, Christoph},
  title     = {Kondensationskernz{\"a}hler in der Reinraummeßtechnik - Meßbereichsgrenzen nach unten verschoben},
  series = {Reinraumtechnik. 5 (1988)},
  journal   = {Reinraumtechnik. 5 (1988)},
  pages     = {36 -- 39},
  year      = {1988},
  language  = {de}
}
@article{Helsper1986,
  author    = {Helsper, Christoph},
  title     = {Kondensationskernz{\"a}hler und ihre Anwendung in der Reinraumtechnik},
  series = {Swiss Chem. 8 (1986)},
  journal   = {Swiss Chem. 8 (1986)},
  isbn      = {0251-1703},
  pages     = {63 -- 66},
  year      = {1986},
  language  = {de}
}
@article{HelsperMoelterMoelter1986,
  author    = {Helsper, Christoph and M{\"o}lter, W. and M{\"o}lter, L.},
  title     = {Korngr{\"o}ßenanalyseverfahren f{\"u}r trockene Pulver und St{\"a}ube von 0,5-25 µm},
  series = {Chemie-Technik. 16 (1986)},
  journal   = {Chemie-Technik. 16 (1986)},
  isbn      = {0340-9961},
  pages     = {140 -- 144},
  year      = {1986},
  language  = {de}
}