@techreport{AdlerHeymerRichteretal.2009,
  author    = {Adler, J. and Heymer, H. and Richter, H. J. and Fend, Th. and Smirnova, O. and Rietbrock, P. and Petchenko, A. and Issendorff, F. v. and Steven, M. and Trimis, D. and Gonsior, Daniel and Helsper, Christoph and Hoffschmidt, Bernhard},
  title     = {INNOTRAP - innovative Rußfilter f{\"u}r LKW-Dieselmotoren : Abschlussbericht F{\"o}rderkennzeichen 16IN0313},
  pages     = {245 S. : Ill., graph. Darst.},
  year      = {2009},
  language  = {de}
}
@article{Helsper1979,
  author    = {Helsper, Christoph},
  title     = {Evaluation of Particle Size Distributions by Means of Particle Counters / Fißan, H. J. ; Helsper, C.},
  series = {Proceedings of the First Workshop of Particulate Control : 16. - 17. March 1978, Kernforschung-sanlage J{\"u}lich GmbH / prepared by U.S. Environmental Protection Agency, Off. of Research and Development, Washington, D.C, 1979,},
  journal   = {Proceedings of the First Workshop of Particulate Control : 16. - 17. March 1978, Kernforschung-sanlage J{\"u}lich GmbH / prepared by U.S. Environmental Protection Agency, Off. of Research and Development, Washington, D.C, 1979,},
  publisher = {Zentralbibliothek d. Kernforschungsanlage J{\"u}lich [in Komm.]},
  address   = {J{\"u}lich},
  pages     = {495 S.: Ill., graph. Darst.},
  year      = {1979},
  language  = {en}
}
@book{Helsper1981,
  author    = {Helsper, Christoph},
  title     = {Bestimmung, Simulation und Korrektur des nichtidealen {\"U}bertragungsverhaltens klassifizierender Aerosolmeßverfahren},
  publisher = {Univ.-Gesamthochsch},
  address   = {Duisburg},
  pages     = {65 S.},
  year      = {1981},
  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{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{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{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}
}