@Article{CH,
  author  = {Roger W. Carter and Trevor O. Hawkes},
  title   = {The {$\cal F$}-normalizers of a finite soluble group},
  journal = {Journal of Algebra},
  volume  = 5,
  number  = 2,
  pages   = {175--202},
  month   = feb,
  year    = 1967
}

@Book{DH,
  author    = {Klaus Doerk and Trevor O. Hawkes},
  title     = {Finite soluble groups},
  publisher = {Walter de Gruyter},
  year      = 1992,
  series    = {De Gruyter Expositions in Mathematics}
}

@Article{EW,
  author  = {Bettina Eick and Charles R. B. Wright},
  title   = {Computing subgroups by exhibition in finite solvable groups},
  journal = {Journal of Symbolic Computation},
  volume  = 33,
  number  = 2,
  pages   = {129--43},
  month   = feb,
  year    = 2002
}

@Article{G,
  author  = {Wolfgang Gasch\"utz},
  title   = {Zur Theorie der endlichen aufl\"osbaren Gruppen},
  journal = {Mathematische Zeitschrift},
  volume  = 80,
  number  = 1,
  pages   = {300--5},
  month   = dec,
  year    = 1963
}

@Article{WA,
  author  = {Charles R. B. Wright},
  title   = {An internal approach to covering groups},
  journal = {Journal of Algebra},
  volume  = 25,
  number  = 1,
  pages   = {128--45},
  month   = apr,
  year    = 1973
}

@Article{WB,
  author  = {Charles R. B. Wright},
  title   = {On internal formation theory},
  journal = {Mathematische Zeitschrift},
  volume  = 134,
  pages   = {1--9},
  month   = mar,
  year    = 1973
}
