@unpublished{SeehaferSchumacher2007,
  author  = {Norbert Seehafer and J{\"o}rg Schumacher},
  title   = {Squire's theorem for the magnetohydrodynamic sheet pinch},
  institution = {Institut f{\"u}r Physik und Astronomie},
  series    = {NLD Preprints},
  number    = {40},
  year    = {2007},
}