@article{HelsperBartzFissanetal.1985,
  author    = {Helsper, Christoph and Bartz, H. and Fißan, H. J. and Kousaka, Y. (u.a.)},
  title     = {Response Characteristics for Four Condensation Nucleus Counters to Particles in the 3 to 50 nm Diameter Range / Bartz, H. ; Fißan, H. J. ; Helsper, C.; Kousaka, Y. ; Okuyama, K. ; Keady, R. Fruin, S. ; McMurry, P. H.; Pui, D. Y. H. ; Stolzenburg, M. R.},
  series = {Journal of Aerosol Science. 16 (1985), H. 5},
  journal   = {Journal of Aerosol Science. 16 (1985), H. 5},
  isbn      = {0021-8502},
  pages     = {443 -- 456},
  year      = {1985},
  language  = {en}
}
@article{HelsperNiessner1985,
  author    = {Helsper, Christoph and Nießner, R.},
  title     = {On the Influence of the Vapour Substance on the Behaviour of an Expansion Type Condensation Nucleus Counter},
  series = {Journal of Aerosol Science. 16 (1985), H. 5},
  journal   = {Journal of Aerosol Science. 16 (1985), H. 5},
  isbn      = {0021-8502},
  pages     = {457 -- 461},
  year      = {1985},
  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{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{HelsperMoelter1987,
  author    = {Helsper, Christoph and M{\"o}lter, W.},
  title     = {Determination and Neutralization of the Charge Produced by the Dispersion of Powders},
  series = {Journal of Aerosol Science. 18 (1987), H. 6},
  journal   = {Journal of Aerosol Science. 18 (1987), H. 6},
  isbn      = {0021-8502},
  pages     = {877 -- 880},
  year      = {1987},
  language  = {de}
}
@article{HelsperMoelterHaller1990,
  author    = {Helsper, Christoph and M{\"o}lter, W. and Haller, P.},
  title     = {Representative Dilution of Aerosols by a Factor of 10,000},
  series = {Journal of Aerosol Science. 21 (1990), H. Suppl. 1},
  journal   = {Journal of Aerosol Science. 21 (1990), H. Suppl. 1},
  isbn      = {0021-8502},
  pages     = {637 -- 640},
  year      = {1990},
  language  = {en}
}
@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{HelsperWiedensohlerWeiseetal.1986,
  author    = {Helsper, Christoph and Wiedensohler, A. and Weise, W. and L{\"u}tkemeier, E.},
  title     = {Determination of the Bipolar Charge Equilibrium in Pure Gases / Wiedensohler, A. ; Weise, W. ; Helsper, C. ; L{\"u}tkemeier, E.},
  series = {Aerosols : formation and reactivity ; proceedings of the second International Aerosol Conference, 22-26 Sept. 1986, Berlin (West) / Gesellschaft f{\"u}r Aerosolforschung (GAeF) ; American Association for Aerosol Research (AAAR)},
  journal   = {Aerosols : formation and reactivity ; proceedings of the second International Aerosol Conference, 22-26 Sept. 1986, Berlin (West) / Gesellschaft f{\"u}r Aerosolforschung (GAeF) ; American Association for Aerosol Research (AAAR)},
  publisher = {Pergamon Press},
  address   = {Oxford [u.a.]},
  pages     = {383 -- 386},
  year      = {1986},
  language  = {en}
}
@article{HelsperLuetkemeierWiedensohler1986,
  author    = {Helsper, Christoph and L{\"u}tkemeier, E. and Wiedensohler, A.},
  title     = {Charge Distribution by Unipolar Charging of Small Aerosol Particles / L{\"u}tkemeier, E. ; Helsper, C. ; Wiedensohler, A.},
  series = {Aerosols : formation and reactivity ; proceedings of the second International Aerosol Conference, 22-26 Sept. 1986, Berlin (West) / Gesellschaft f{\"u}r Aerosolforschung (GAeF) ; American Association for Aerosol Research (AAAR)},
  journal   = {Aerosols : formation and reactivity ; proceedings of the second International Aerosol Conference, 22-26 Sept. 1986, Berlin (West) / Gesellschaft f{\"u}r Aerosolforschung (GAeF) ; American Association for Aerosol Research (AAAR)},
  publisher = {Pergamon Press},
  address   = {Oxford [u.a.]},
  pages     = {474 -- 478},
  year      = {1986},
  language  = {en}
}
@article{Helsper1986,
  author    = {Helsper, Christoph},
  title     = {Measurement Techniques For Ultrafine Particles},
  series = {Ultrafine aerosols. Properties and behaviour. Proceedings of the 1. International Workshop on Ultrafine Aerosols of the Sonderforschungsbereich 209 'Stoff- und Energietransport in Aerosolen' -'Mass and energy transfer in aerosols'-, held at the Univ. of Duisburg on Sept. 29, 1986},
  journal   = {Ultrafine aerosols. Properties and behaviour. Proceedings of the 1. International Workshop on Ultrafine Aerosols of the Sonderforschungsbereich 209 'Stoff- und Energietransport in Aerosolen' -'Mass and energy transfer in aerosols'-, held at the Univ. of Duisburg on Sept. 29, 1986},
  address   = {Duisburg},
  year      = {1986},
  language  = {en}
}
@article{HelsperBartz1987,
  author    = {Helsper, Christoph and Bartz, H.},
  title     = {Theoretische Bestimmung des Abscheidegrades eines Filters bei verschiedenen Betriebszust{\"a}nden / Bartz, H. ; Helsper, C.},
  series = {Staub, Reinhaltung der Luft. 47 (1987)},
  journal   = {Staub, Reinhaltung der Luft. 47 (1987)},
  isbn      = {0039-0771},
  pages     = {112 -- 114},
  year      = {1987},
  language  = {de}
}
@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{Helsper1995,
  author    = {Helsper, Christoph},
  title     = {Probleme der Staubprobenahme bei der Filterpr{\"u}fung},
  series = {Filtrieren und Separieren (1995)},
  journal   = {Filtrieren und Separieren (1995)},
  isbn      = {0933-5927},
  pages     = {5 -- 13},
  year      = {1995},
  language  = {de}
}
@article{Helsper2002,
  author    = {Helsper, Christoph},
  title     = {Partikelmesstechnik},
  series = {Reinraumtechnik , Hrsg.: Gail, Lothar},
  journal   = {Reinraumtechnik , Hrsg.: Gail, Lothar},
  publisher = {Springer},
  address   = {Berlin [u.a.]},
  isbn      = {3-540-66885-3},
  pages     = {57 -- 82},
  year      = {2002},
  language  = {de}
}
@article{Helsper2003,
  author    = {Helsper, Christoph},
  title     = {Messverfahren zur Charakterisierung der Abscheidung luftgetragener Partikel in Filtern},
  series = {Schutzmaßnahmen vor mikrobiellen Belastungen des Innenraumes / VII. L{\"u}becker Fachtagung f{\"u}r Umwelthygiene. [Hrsg.:] Reinhard Keller ...},
  journal   = {Schutzmaßnahmen vor mikrobiellen Belastungen des Innenraumes / VII. L{\"u}becker Fachtagung f{\"u}r Umwelthygiene. [Hrsg.:] Reinhard Keller ...},
  publisher = {Inst. f. Medizinische Mikrobiologie u. Hygiene d. Med. Univ.},
  address   = {L{\"u}beck},
  pages     = {35 -- 61},
  year      = {2003},
  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}
}
@article{HelsperMoelterWillemer1987,
  author    = {Helsper, Christoph and M{\"o}lter, W. and Willemer, W.},
  title     = {Fast and Automated Testing of Filter Media / M{\"o}lter, W. ; Helsper, C. ; Willemer, W.},
  series = {FILTECH Conference 1987 : Utrecht, Holland; September 23 - 25 1987 / org. by the Filtration Society , Vol. 1.},
  journal   = {FILTECH Conference 1987 : Utrecht, Holland; September 23 - 25 1987 / org. by the Filtration Society , Vol. 1.},
  publisher = {Filtration Society},
  address   = {Loughborough},
  pages     = {106 -- 112},
  year      = {1987},
  language  = {en}
}
@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{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}
}