@book{Liebers1995,
  author    = {Liebers, Klaus},
  title     = {Optische Ger{\"a}te},
  series = {Naturwissenschaften : Biologie, Chemie, Physik},
  journal   = {Naturwissenschaften : Biologie, Chemie, Physik},
  publisher = {Volk und Wissen},
  address   = {Berlin},
  pages     = {80 S.},
  year      = {1995},
  language  = {de}
}
@book{Liebers1999,
  author    = {Liebers, Klaus},
  title     = {Physik plus : Kl. 7/8, [Hauptbd.], Sek. 1 Sachsen},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Volk-und-Wissen-Verl.},
  address   = {Berlin},
  isbn      = {3-06-020741-0},
  pages     = {216 S.},
  year      = {1999},
  language  = {de}
}
@book{Liebers2000,
  author    = {Liebers, Klaus},
  title     = {Physik plus : Kl. 8, Arbeitsh., Gymnasium Th{\"u}ringen},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Cornelsen},
  address   = {Berlin},
  isbn      = {3-06-020841-7},
  pages     = {40 S.},
  year      = {2000},
  language  = {de}
}
@book{Liebers2000,
  author    = {Liebers, Klaus},
  title     = {Physik plus : mit f{\"a}cher{\"u}bergreifenden Themen und Projektangeboten ; Kl. 7/8, [Hauptbd.], Gymnasium Th{\"u}ringen},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Cornelsen},
  address   = {Berlin},
  isbn      = {3-06-020743-7},
  pages     = {248 S.},
  year      = {2000},
  language  = {de}
}
@book{Liebers2000,
  author    = {Liebers, Klaus},
  title     = {Physik plus : mit f{\"a}cher{\"u}bergreifenden Themen und Projektangeboten ; Kl. 7/8, Lehrerbd., mit Kopiervorlagen und L{\"o}sungen zu den Arbeitsheften, Gymnasium Th{\"u}ringen},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Cornelsen},
  address   = {Berlin},
  isbn      = {3-06-022261-4},
  pages     = {118 S.},
  year      = {2000},
  language  = {de}
}
@book{Liebers2000,
  author    = {Liebers, Klaus},
  title     = {Physik plus : mit f{\"a}cher{\"u}bergreifenden Themen und Projektangeboten ; Kl. 7/8, [Hauptbd.], Gymnasium Sachsen-Anhalt},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Volk-und-Wissen-Verl.},
  address   = {Berlin},
  isbn      = {3-06-020742-9},
  pages     = {216 S.},
  year      = {2000},
  language  = {de}
}
@book{Liebers2000,
  author    = {Liebers, Klaus},
  title     = {Physik plus : Kl. 7, Arbeitsh., Gymnasium Th{\"u}ringen},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Cornelsen},
  address   = {Berlin},
  isbn      = {3-06-020771-2},
  pages     = {40 S.},
  year      = {2000},
  language  = {de}
}
@book{Liebers2001,
  author    = {Liebers, Klaus},
  title     = {Physik plus : mit f{\"a}cher{\"u}bergreifenden Themen und Projektangeboten ; Kl. 6, Mecklenburg-Vorpommern},
  editor    = {Mikelskis, Klaus and Wilke, Hans-Joachim},
  publisher = {Volk-und-Wissen-Verl.},
  address   = {Berlin},
  isbn      = {3-06-020628-7},
  pages     = {80 S.},
  year      = {2001},
  language  = {de}
}
@book{Liebers2001,
  author    = {Liebers, Klaus},
  title     = {Physik : Kl. 7/8, [Hauptbd.], Sekundarschule Sachsen-Anhalt},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Volk-und-Wissen-Verl.},
  address   = {Berlin},
  isbn      = {3-06-020734-8},
  pages     = {192 S.},
  year      = {2001},
  language  = {de}
}
@book{Liebers2001,
  author    = {Liebers, Klaus},
  title     = {Physik : Kl. 7/8, Arbeitsh., Sekundarschule Sachsen-Anhalt},
  editor    = {Mikelskis, Helmut and Wilke, Hans-Joachim},
  publisher = {Volk-und-Wissen-Verl.},
  address   = {Berlin},
  isbn      = {3-06-020737-2},
  pages     = {48 S.},
  year      = {2001},
  language  = {de}
}