update reference

RalfJung · RalfJung · commit 4dd60f3114ce · 2019-09-09T20:48:57.000+02:00
diff --git a/src/doc/reference b/src/doc/reference
@@ -1 +1 @@
-Subproject commit 090c015f7939665866432c334957bd536c811870
+Subproject commit 1944efed35989ba57fa397c0724c4921310311fc
