@Book{Soga,
ALTauthor = {•},
editor = {T. Soga},
title = {Nanostructured Materials for Solar Energy Conversion},
publisher = {Elsevier Science},
year = {2006},
OPTkey = {•},
OPTvolume = {•},
OPTnumber = {•},
OPTseries = {•},
address = {Netherlands},
edition = {1st},
OPTmonth = {•},
OPTnote = {•},
OPTannote = {•}
}

@Article{Gratzelnature,
author = {M. Gr\"atzel and B. O'Regan},
OPTtitle = {},
journal = {Nature},
year = {1991},
OPTkey = {},
volume = {\textbf{353}},
OPTnumber = {},
pages = {$\,$737},
OPTmonth = {},
OPTnote = {},
OPTannote = {}
}

@Article{Hagfeldt,
author = {A. Hagfeldt and G. Boschloo and L. Sun and L. Kloo and H. Pettersson},
OPTtitle = {},
journal = {Chem. Rev.},
year = {2010},
OPTkey = {},
volume = {\textbf{110}},
number = {11},
pages = {$\,$6595},
OPTmonth = {},
OPTnote = {},
OPTannote = {}
}

@Book{Wurfel,
author = {Peter W\"urfel},
ALTeditor = {},
title = {Physics of Solar Cells: From Principles to New Concepts},
publisher = {Wiley-VCH},
year = {2005},
OPTkey = {•},
OPTvolume = {•},
OPTnumber = {•},
OPTseries = {•},
address = {Germany},
OPTedition = {},
OPTmonth = {•},
OPTnote = {•},
OPTannote = {•}
}