diff --git a/prototype/src/main/resources/static/js/back.js b/prototype/src/main/resources/static/js/back.js
index 9f41110..1c29cd2 100644
--- a/prototype/src/main/resources/static/js/back.js
+++ b/prototype/src/main/resources/static/js/back.js
@@ -9,13 +9,13 @@ document.addEventListener("DOMContentLoaded", function(event) {
    let insert = back.dataset.insert == "true";
 
    if (name) {
-      window.sessionStorage.setItem('back-' + 'group', JSON.stringify({
+      window.sessionStorage.setItem('back-' + group, JSON.stringify({
          'text': name,
          'location': window.location.toString()
       }));
    }
 
-   let history = JSON.parse(window.sessionStorage.getItem('back-' + 'group'));
+   let history = JSON.parse(window.sessionStorage.getItem('back-' + group));
    if (insert && history) {
 
       let a = document.createElement("a");