Fix reference in c6 using \@(label) notation
Fix reference in c6 using \@(label) notation

modumont/spatial-microsim-book,Robinlovelace/spatial-microsim-book,Robinlovelace/spatial-microsim-book,Robinlovelace/spatial-microsim-book,modumont/spatial-microsim-book,modumont/spatial-microsim-book