diff --git a/test/spec.txt b/test/spec.txt
@@ -2033,6 +2033,15 @@ This is not a link reference definition, because there are
<p>[foo]: /url "title" ok</p>
.
+This is a link reference definition, but it has no title:
+
+.
+[foo]: /url
+"title" ok
+.
+<p>"title" ok</p>
+.
+
This is not a link reference definition, because it is indented
four spaces:
@@ -5833,7 +5842,9 @@ A [link text](@link-text) consists of a sequence of zero or more
inline elements enclosed by square brackets (`[` and `]`). The
following rules apply:
-- Links may not contain other links, at any level of nesting.
+- Links may not contain other links, at any level of nesting. If
+ multiple otherwise valid link definitions appear nested inside each
+ other, the inner-most definition is used.
- Brackets are allowed in the [link text] only if (a) they
are backslash-escaped or (b) they appear as a matched pair of brackets,