diff --git a/annotations/yo/cplusplus.yo b/annotations/yo/cplusplus.yo
index c532f943..0e90d752 100644
--- a/annotations/yo/cplusplus.yo
+++ b/annotations/yo/cplusplus.yo
@@ -116,6 +116,11 @@ COMMENT( 20 )
 lchapter(THREADING)(Multi Threading)
 includefile(threading)
 
+lchapter( 21 )
+chapter(Coroutines)
+COMMENT(FBB: TODO, and update chapters below. See
+            http://www.boost.org/doc/libs/1_66_0/libs/coroutine2/doc/html)
+
 COMMENT( 21 )
 lchapter(TEMPLATES)(Function and Variable Templates)
 includefile(functiontemplates)