diff --git a/js/collapse.js b/js/collapse.js
index ab575515de..b20022a2e5 100644
--- a/js/collapse.js
+++ b/js/collapse.js
@@ -169,7 +169,7 @@
     var $parent = parent && $(parent)
 
     if (!data || !data.transitioning) {
-      if ($parent) $parent.find('[data-toggle=collapse][data-parent=' + parent + ']').not($this).addClass('collapsed')
+      if ($parent) $parent.find('[data-toggle=collapse][data-parent="' + parent + '"]').not($this).addClass('collapsed')
       $this[$target.hasClass('in') ? 'addClass' : 'removeClass']('collapsed')
     }