1\version "2.19.21"
2\header {
3  texidoc = "Contexts of the same type can be nested."
4}
5
6\new StaffGroup \relative <<
7  \new Staff { c'1 }
8  \new StaffGroup <<
9    \new Staff { c1 }
10    \new StaffGroup <<
11      \new Staff { c1 }
12      \new Staff { c1 }
13    >>
14  >>
15>>
16