Fix reference error

Author: Sonja Broda

composer.json

@@ -1,7 +1,7 @@
 {
     "name": "texnixe/related",
     "description": "Fetch related pages or files based on the values of a given field ",
-    "version": "0.9.0",
+    "version": "0.9.1",
     "type": "kirby-plugin",
     "license": "MIT",
     "authors": [

index.php

@@ -2,7 +2,7 @@
 /**
  * Kirby 3 Related Pages Plugin
  *
- * @version   0.9.0
+ * @version   0.9.1
  * @author    Sonja Broda <info@texniq.de>
  * @copyright Sonja Broda <info@texniq.de>
  * @link      https://github.com/texnixe/kirby-related

package.json

@@ -3,7 +3,7 @@
   "description": "Kirby Related plugin",
   "author": "Sonja Broda <sonja@texniq.de>",
   "license": "MIT",
-  "version": "0.9.0",
+  "version": "0.9.1",
   "repository": {
     "type": "git",
     "url": "https://github.com/texnixe/kirby-related"

src/Related.php

@@ -2,6 +2,7 @@
 
 namespace Texnixe\Related;
 
+
 class Related
 {
 
@@ -41,7 +42,7 @@ public static function data($basis, $options = [])
         // define variables
         $searchCollection = $options['searchCollection'];
         $matches          = $options['matches'];
-        $searchField      = str::lower($options['searchField']);
+        $searchField      = strtolower($options['searchField']);
         $delimiter        = $options['delimiter'];
         $languageFilter   = $options['languageFilter'];