\version "2.19.15"

myMusic = { \repeat unfold 60 a' }

\score {
  \new StaffGroup <<
    <<
      \new Staff = Un { \new Voice = un { \myMusic } }
      \new Lyrics 
        \lyricsto un { \repeat unfold 60 bla }
      \new Lyrics \with { alignAboveContext = Un }
        \lyricsto un { \repeat unfold 16 \skip 1 \repeat unfold 10 \markup\italic glou }
    >>
    <<
      \new Staff = Deux { \new Voice = deux { \myMusic } }
      \new Lyrics 
        \lyricsto deux { \repeat unfold 60 bla }
      \new Lyrics \with { alignAboveContext = Deux }
        \lyricsto deux { \repeat unfold 20 \skip 1 \repeat unfold 10 \markup\italic glou }
    >> 
    <<
      \new Staff = Trois { \new Voice = trois { \myMusic } }
      \new Lyrics 
        \lyricsto trois { \repeat unfold 60 bla }
      \new Lyrics \with { alignAboveContext = Trois }
        \lyricsto trois { \repeat unfold 32 \skip 1 \repeat unfold 10 \markup\italic glou }
    >>
    <<
      \new Staff = Quatre { \new Voice = quatre { \myMusic } }
      \new Lyrics 
        \lyricsto quatre { \repeat unfold 60 bla }
      \new Lyrics \with { alignAboveContext = Quatre }
        \lyricsto quatre { \repeat unfold 48 \skip 1 \repeat unfold 10 \markup\italic glou }
    >>
 >>
}