\version "2.18.2"

\score {
  <<
    \new StaffGroup <<
      \new Staff { 
        \set Score.repeatCommands = #(list 
           (list 'volta 
             #{ \markup\text\bold\concat { 
               \hspace #2 
               "Entweder" \hspace #.1 ":"} #}) 
           'end-repeat)
        R1 R 
        \set Score.repeatCommands = #'((volta #f))
        \bar "|." 
      } 
      \new Staff { R1 R }
      \new Staff { R1 R }
      \new Staff { \clef F R1 R }
      \new GrandStaff <<
        \new Staff { R1 R }
        \new Staff { R1 R  }
      >>
      \new Staff { R1 R }
      \new Staff { \clef F R1 R }
      \new GrandStaff <<
        \new Staff { R1 R }
        \new Staff { R1 R }
      >>
    \new Staff { \clef C R1 R }
    >>
    \new GrandStaff <<
      \new Staff { R1 R }
      \new Staff { R1 R }
    >> 
    \new GrandStaff <<
      \new Staff { \clef F R1 R }
      \new Staff { \clef F R1 R }
    >>
  >>
  \layout {
    line-width = 80
    ragged-right = ##f
  }
}