diff --git a/src/Utils/SchemaPrinter.php b/src/Utils/SchemaPrinter.php
index 57d4c6f..be82fec 100644
--- a/src/Utils/SchemaPrinter.php
+++ b/src/Utils/SchemaPrinter.php
@@ -351,7 +351,7 @@ class SchemaPrinter
         $interfaces            = $type->getInterfaces();
         $implementedInterfaces = ! empty($interfaces) ?
             ' implements ' . implode(
-                '& ',
+                ' & ',
                 array_map(
                     function ($i) {
                         return $i->name;