@article{HoffschmidtFendJorgensenetal.2003,
  author    = {Hoffschmidt, Bernhard and Fend, Thomas and Jorgensen, Gary and K{\"u}ster, Harald},
  title     = {Comparative assessment of solar concentrator materials / Fend, Thomas ; Hoffschmidt, Bernhard ; Jorgensen, Gary ; K{\"u}ster, Harald ; Kr{\"u}ger, Dirk ; Pitz-Paal, Robert ; Riebrock, Peter ; Riffelmann, Klaus-J{\"u}rgen},
  series = {Solar energy. 74 (2003), H. 2},
  journal   = {Solar energy. 74 (2003), H. 2},
  isbn      = {0038-092X},
  pages     = {149 -- 155},
  year      = {2003},
  language  = {en}
}
@article{HoffschmidtTellezValverdeetal.2003,
  author    = {Hoffschmidt, Bernhard and T{\´e}llez, F{\´e}lix M. and Valverde, Antonio and Fernandez, Valerio and Fernandez, Jesus},
  title     = {Performance evaluation of the 200-kWth HiTRec-II open volumetric air receiver},
  series = {Journal of solar energy engineering},
  volume    = {Vol. 125},
  journal   = {Journal of solar energy engineering},
  number    = {Iss. 1},
  pages     = {87 -- 94},
  year      = {2003},
  language  = {en}
}