@article{HoffschmidtFendPitzPaaletal.2004,
  author    = {Hoffschmidt, Bernhard and Fend, Thomas and Pitz-Paal, Robert and Reutter, Oliver},
  title     = {Two novel high-porosity materials as volumetric receivers for concentrated solar radiation / Thomas Fend ; Robert Pitz-Paal ; Oliver Reutter ... Bernhard Hoffschmidt},
  series = {Solar energy materials \& solar cells. 84 (2004), H. 1},
  journal   = {Solar energy materials \& solar cells. 84 (2004), H. 1},
  isbn      = {0927-0248},
  pages     = {291 -- 304},
  year      = {2004},
  language  = {en}
}
@article{HoffschmidtFendPitzPaaletal.2004,
  author    = {Hoffschmidt, Bernhard and Fend, Thomas and Pitz-Paal, Robert and Reutter, Oliver},
  title     = {Porous materials as open volumetric solar receivers - Experimental determination of thermophysical and heat transfer properties / Thomas Fend ; Bernhard Hoffschmidt ...},
  series = {Energy. 29 (2004), H. 5},
  journal   = {Energy. 29 (2004), H. 5},
  isbn      = {0360-5442},
  pages     = {823 -- 834},
  year      = {2004},
  language  = {en}
}
@article{HoffschmidtPitzPaalBoehmer1999,
  author    = {Hoffschmidt, Bernhard and Pitz-Paal, Robert and B{\"o}hmer, M.},
  title     = {A new closed/open volumetric receiver concept for parabolictrough collectors (test results)},
  series = {Journal de physique. 9 (1999), H. 3},
  journal   = {Journal de physique. 9 (1999), H. 3},
  isbn      = {1155-4339},
  pages     = {3},
  year      = {1999},
  language  = {en}
}