@article{HelsperFissan1979,
  author    = {Helsper, Christoph and Fißan, H. J.},
  title     = {Numerical Simulation Studies and Data Reduction for Size Classifying Measurement Techniques / Fißan, H. J.; Helsper, C.},
  series = {Aerosols in science, medicine and technology : conference / Gesellschaft f{\"u}r Aerosolforschung 7. 1979.},
  journal   = {Aerosols in science, medicine and technology : conference / Gesellschaft f{\"u}r Aerosolforschung 7. 1979.},
  pages     = {199 -- 205},
  year      = {1979},
  language  = {en}
}
@article{HelsperFissan1980,
  author    = {Helsper, Christoph and Fißan, H. J.},
  title     = {Numerical Simulation Studies and Data Reduction for Size Classifying Measurement Techniques / Fißan, H. J.; Helsper, C.},
  series = {Advances in Particle Sampling and Measurement: Proceedings, Daytona Beach, EPA 600/9 80 004, 1980},
  journal   = {Advances in Particle Sampling and Measurement: Proceedings, Daytona Beach, EPA 600/9 80 004, 1980},
  publisher = {National Technical Information Service},
  address   = {Springfield, Va.},
  pages     = {VII, 409 S.},
  year      = {1980},
  language  = {en}
}
@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{HelsperFissan1982,
  author    = {Helsper, Christoph and Fißan, H. J.},
  title     = {Techniken zur Kalibrierung von Staubmeßger{\"a}ten / Fißan, H. J.; Helsper, C.},
  series = {Schwebstoffe und St{\"a}ube : analyt. u. techn. Aspekte ; Kolloquium N{\"u}rnberg 1981},
  journal   = {Schwebstoffe und St{\"a}ube : analyt. u. techn. Aspekte ; Kolloquium N{\"u}rnberg 1981},
  publisher = {VDI-Verl.},
  address   = {D{\"u}sseldorf},
  isbn      = {3-18-090429-1},
  pages     = {59 -- 64},
  year      = {1982},
  language  = {de}
}
@article{HelsperFissan1982,
  author    = {Helsper, Christoph and Fißan, H. J.},
  title     = {Zur Reaktion von Rauchdetektoren auf Brandkenngr{\"o}ßen / Fißan, H. J.; Helsper, C.},
  series = {Tagungsbericht zum Internationalen Vortragsseminar {\"u}ber Probleme der automatischen Brandent-deckung / Institut f{\"u}r Elektrische Nachrichtentechnik. Technische Hochschule Aachen ; Fachgebiet Nachrichtentechnik. Universit{\"a}t Duisburg, Gesamthochschule . 8. Internationales Vortragsseminar "AUBE 82"},
  journal   = {Tagungsbericht zum Internationalen Vortragsseminar {\"u}ber Probleme der automatischen Brandent-deckung / Institut f{\"u}r Elektrische Nachrichtentechnik. Technische Hochschule Aachen ; Fachgebiet Nachrichtentechnik. Universit{\"a}t Duisburg, Gesamthochschule . 8. Internationales Vortragsseminar "AUBE 82"},
  address   = {Duisburg},
  pages     = {20 -- 37},
  year      = {1982},
  language  = {de}
}
@article{HelsperFissan1983,
  author    = {Helsper, Christoph and Fißan, H. J.},
  title     = {Calibration of the Polytec HC-15 and HC-70 Optical Particle Counters / Fißan, H. J. ; Helsper, C.},
  series = {Aerosols in the mining and industrial work environments, Vol. 3. Instrumentation, Marple, Virgil A. ; Liu, Benjamin Y.},
  journal   = {Aerosols in the mining and industrial work environments, Vol. 3. Instrumentation, Marple, Virgil A. ; Liu, Benjamin Y.},
  publisher = {Ann Arbor Science},
  address   = {Ann Arbor, Mich.},
  pages     = {825 -- 829},
  year      = {1983},
  language  = {en}
}
@article{HelsperFissanFranzen1976,
  author    = {Helsper, Christoph and Fißan, H. J. and Franzen, H.},
  title     = {Bestimmung der Gr{\"o}ßenverteilung von Aerosolen aus Verbrennungsvorg{\"a}ngen mit einem elektrostatischen Aerosolanalysator},
  series = {Aerosole in Naturwissenschaft, Medizin und Technik : Bericht der Tagung der Gesellschaft f{\"u}r Aerosolforschung e.V. 4, 1976},
  journal   = {Aerosole in Naturwissenschaft, Medizin und Technik : Bericht der Tagung der Gesellschaft f{\"u}r Aerosolforschung e.V. 4, 1976},
  pages     = {118 -- 126},
  year      = {1976},
  language  = {de}
}
@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{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{HelsperFissanKasper1984,
  author    = {Helsper, Christoph and Fißan, H. J. and Kasper, W.},
  title     = {Calibration of Optical Particle Counters with Respect to Particle Size / Fißan, H. J. ; Helsper, C.; Kasper, W.},
  series = {Particle and Particle Systems Characterization. 1 (1984), H. 1984},
  journal   = {Particle and Particle Systems Characterization. 1 (1984), H. 1984},
  isbn      = {1521-4117},
  pages     = {108 -- 111},
  year      = {1984},
  language  = {en}
}
@article{HelsperFissanMugglietal.1980,
  author    = {Helsper, Christoph and Fißan, H. J. and Muggli, J. and Scheidweiler, A.},
  title     = {Particle Number Distributions of Aerosols from Test Fires},
  series = {Journal of Aerosol Science. 11 (1980), H. 5-6},
  journal   = {Journal of Aerosol Science. 11 (1980), H. 5-6},
  isbn      = {0021-8502},
  pages     = {439 -- 446},
  year      = {1980},
  language  = {en}
}
@article{HelsperFissanMugglietal.1983,
  author    = {Helsper, Christoph and Fißan, H. J. and Muggli, J. and Scheidweiler, A.},
  title     = {Verification of Ionization Chamber Theory},
  series = {Fire Technology. 19 (1983), H. 1},
  journal   = {Fire Technology. 19 (1983), H. 1},
  isbn      = {1572-8099},
  pages     = {14 -- 21},
  year      = {1983},
  language  = {en}
}
@article{HelsperFissanThielen1983,
  author    = {Helsper, Christoph and Fißan, H. J. and Thielen, H. J.},
  title     = {Determination of Particle Size Distributions by Means of an Electrostatic Classifier / Fißan, H. J.; Helsper, C. ; Thielen, H. J.},
  series = {Journal of Aerosol Science. 14 (1983), H. 3},
  journal   = {Journal of Aerosol Science. 14 (1983), H. 3},
  isbn      = {0021-8502},
  pages     = {354 -- 357},
  year      = {1983},
  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{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{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{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{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}
}
@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{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}
}