@article{KotterHammonRiekert1989,
  author    = {Kotter, Michael and Hammon, Ulrich and Riekert, Lothar},
  title     = {Gewinnung niedriger Olefine aus Methanol bei partiellem Umsatz mit R{\"u}ckf{\"u}hrung / U. Hammon ; M. Kotter ; L. Riekert},
  series = {Chemie - Ingenieur - Technik. 61 (1989), H. 2},
  journal   = {Chemie - Ingenieur - Technik. 61 (1989), H. 2},
  isbn      = {0009-286X},
  pages     = {151 -- 152},
  year      = {1989},
  language  = {de}
}
@article{KotterRiekertTurek1989,
  author    = {Kotter, Michael and Riekert, Lothar and Turek, Thomas},
  title     = {Entfernung von Ammoniak aus Abw{\"a}ssern durch Strippung und Sorption an Zeolithen : [Synopse 1724]},
  series = {Chemie - Ingenieur - Technik. 61 (1989), H. 1},
  journal   = {Chemie - Ingenieur - Technik. 61 (1989), H. 1},
  isbn      = {0009-286X},
  pages     = {74 -- 75},
  year      = {1989},
  language  = {de}
}
@article{KotterBeckerRiekert1989,
  author    = {Kotter, Michael and Becker, Dieter and Riekert, Lothar},
  title     = {Zur Selektivit{\"a}t der partiellen Oxidation von Propen an Schalenkatalysatoren / Dieter Becker ; Michael Kotter ; Lothar Riekert},
  series = {Chemie - Ingenieur - Technik. 61 (1989), H. 9},
  journal   = {Chemie - Ingenieur - Technik. 61 (1989), H. 9},
  isbn      = {0009-286X},
  pages     = {748 -- 749},
  year      = {1989},
  language  = {de}
}
@article{Alt1989,
  author    = {Alt, Helmut},
  title     = {Die Bedeutung des Effektivzinses in der Finanzwirtschaft},
  series = {Betriebs-Berater : BB : Beil. 14 Finanz-Berater},
  journal   = {Betriebs-Berater : BB : Beil. 14 Finanz-Berater},
  issn      = {0340-7926},
  pages     = {31 -- 32},
  year      = {1989},
  language  = {de}
}
@article{Alt1989,
  author    = {Alt, Helmut},
  title     = {Einfluß der Kontof{\"u}hrungsmodelle auf den Effektivzins und die Restschuld bei Annuit{\"a}tendarlehen},
  series = {Betriebs-Berater : BB : Beil. 14 Finanz-Berater},
  journal   = {Betriebs-Berater : BB : Beil. 14 Finanz-Berater},
  issn      = {0340-7926},
  pages     = {32 -- 37},
  year      = {1989},
  language  = {de}
}
@article{Alt1989,
  author    = {Alt, Helmut},
  title     = {Steuerreformgesetz 1990},
  series = {Elektrizit{\"a}tswirtschaft},
  volume    = {Bd. 88},
  journal   = {Elektrizit{\"a}tswirtschaft},
  number    = {H. 1/2},
  issn      = {0013-5496},
  pages     = {78 -- 83},
  year      = {1989},
  language  = {de}
}
@article{Alt1989,
  author    = {Alt, Helmut},
  title     = {Steuerreformgesetz 1990},
  series = {Elektrizit{\"a}tswirtschaft},
  volume    = {Jg. 88},
  journal   = {Elektrizit{\"a}tswirtschaft},
  number    = {H. 2},
  issn      = {0947-0581 (E-Journal); 0340-7918 (Print)},
  pages     = {120 -- 121},
  year      = {1989},
  language  = {de}
}
@article{SaffeLodewiksHaasetal.1989,
  author    = {Saffe, P. and Lodewiks, J. and Haas, H.-J. and Feigel, H.-J. and Ulrich, H. and Mauer, J. and Ortwig, H. and Dahmann, Peter and Rotth{\"a}user, S. and Tao, J. and Ohlischl{\"a}ger, O. and Scholz, D. and Bergmann, M. and Anders, P.},
  title     = {Neues von ASB Antreiben - Steuern - Bewegen},
  series = {{\"O}lhydraulik und Pneumatik. Vol. 33 (1989), H. 7},
  journal   = {{\"O}lhydraulik und Pneumatik. Vol. 33 (1989), H. 7},
  issn      = {0341-2660},
  pages     = {550 -- 572},
  year      = {1989},
  language  = {de}
}
@article{LaackCasser1989,
  author    = {Laack, Walter van and Casser, H.-R.},
  title     = {Arthroskopische Behandlung der Osteochondrosis dissecans an der medialen Femurrolle},
  series = {Arthroskopie. 2 (1989), H. 1},
  journal   = {Arthroskopie. 2 (1989), H. 1},
  isbn      = {0933-7946},
  pages     = {16 -- 18},
  year      = {1989},
  language  = {de}
}
@article{StaatBallmann1989,
  author    = {Staat, Manfred and Ballmann, J.},
  title     = {Zur Problematik tensorieller Verallgemeinerungen einachsiger nichtlinearer Materialgesetze},
  series = {Zeitschrift f{\"u}r angewandte Mathematik und Mechanik : ZAMM. 69 (1989), H. 2},
  journal   = {Zeitschrift f{\"u}r angewandte Mathematik und Mechanik : ZAMM. 69 (1989), H. 2},
  isbn      = {0946-8463},
  doi       = {10.1515/9783112553169-006},
  pages     = {73 -- 81},
  year      = {1989},
  language  = {de}
}