diff --git a/CHANGELOG.md b/CHANGELOG.md
index b7c980da..1aea5b3a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -27,7 +27,7 @@ Please also have a look at our
 - Make all non-private properties `@internal` (#886)
 - Use more native type declarations and strict mode
   (#641, #772, #774, #778, #804, #841, #873, #875, #891, #922, #923, #933, #958,
-  #964)
+  #964, #967)
 - Add visibility to all class/interface constants (#469)
 
 ### Deprecated
diff --git a/src/CSSList/CSSList.php b/src/CSSList/CSSList.php
index e7acc842..bc4f43df 100644
--- a/src/CSSList/CSSList.php
+++ b/src/CSSList/CSSList.php
@@ -470,7 +470,7 @@ public function addComments(array $comments): void
     /**
      * @return array<array-key, Comment>
      */
-    public function getComments()
+    public function getComments(): array
     {
         return $this->comments;
     }
diff --git a/src/Comment/Commentable.php b/src/Comment/Commentable.php
index 0cb3df24..5e0fba97 100644
--- a/src/Comment/Commentable.php
+++ b/src/Comment/Commentable.php
@@ -14,7 +14,7 @@ public function addComments(array $comments): void;
     /**
      * @return array<array-key, Comment>
      */
-    public function getComments();
+    public function getComments(): array;
 
     /**
      * @param array<array-key, Comment> $comments
diff --git a/src/Property/CSSNamespace.php b/src/Property/CSSNamespace.php
index 81f24e34..21135a35 100644
--- a/src/Property/CSSNamespace.php
+++ b/src/Property/CSSNamespace.php
@@ -128,7 +128,7 @@ public function addComments(array $comments): void
     /**
      * @return array<array-key, Comment>
      */
-    public function getComments()
+    public function getComments(): array
     {
         return $this->comments;
     }
diff --git a/src/Property/Charset.php b/src/Property/Charset.php
index 20522739..ac063f28 100644
--- a/src/Property/Charset.php
+++ b/src/Property/Charset.php
@@ -105,7 +105,7 @@ public function addComments(array $comments): void
     /**
      * @return array<array-key, Comment>
      */
-    public function getComments()
+    public function getComments(): array
     {
         return $this->comments;
     }
diff --git a/src/Property/Import.php b/src/Property/Import.php
index bc97d949..8240e28f 100644
--- a/src/Property/Import.php
+++ b/src/Property/Import.php
@@ -111,7 +111,7 @@ public function addComments(array $comments): void
     /**
      * @return array<array-key, Comment>
      */
-    public function getComments()
+    public function getComments(): array
     {
         return $this->comments;
     }
diff --git a/src/Rule/Rule.php b/src/Rule/Rule.php
index a2cbbb86..f4803b77 100644
--- a/src/Rule/Rule.php
+++ b/src/Rule/Rule.php
@@ -294,7 +294,7 @@ public function addComments(array $comments): void
     /**
      * @return array<array-key, Comment>
      */
-    public function getComments()
+    public function getComments(): array
     {
         return $this->comments;
     }
diff --git a/src/RuleSet/RuleSet.php b/src/RuleSet/RuleSet.php
index 8e9cf1aa..b5306c39 100644
--- a/src/RuleSet/RuleSet.php
+++ b/src/RuleSet/RuleSet.php
@@ -305,7 +305,7 @@ public function addComments(array $comments): void
     /**
      * @return array<string, Comment>
      */
-    public function getComments()
+    public function getComments(): array
     {
         return $this->comments;
     }