diff --git a/History.js b/History.js
index 824303d7b..10ad588bd 100644
--- a/History.js
+++ b/History.js
@@ -53,6 +53,10 @@
     let previousNotesSetKey;
     let currentNotesSetKey;
 
+    let offsetChangedEventSubscriptionId
+    let filesUpdatedEventSubscriptionId
+    let dimmensionsChangedEventSubscriptionId
+
     return thisObject;
 
     function finalize() {
@@ -62,9 +66,9 @@
 
             /* Stop listening to the necesary events. */
 
-            viewPort.eventHandler.stopListening("Offset Changed", onOffsetChanged);
-            marketFiles.eventHandler.stopListening("Files Updated", onFilesUpdated);
-            thisObject.container.eventHandler.stopListening('Dimmensions Changed')
+            viewPort.eventHandler.stopListening(offsetChangedEventSubscriptionId);
+            fileSequence.eventHandler.stopListening(filesUpdatedEventSubscriptionId);
+            thisObject.container.eventHandler.stopListening(dimmensionsChangedEventSubscriptionId)
 
             /* Destroyd References */
 
@@ -96,10 +100,10 @@
             recalculate(callBackFunction);
             recalculateScale(callBackFunction);
 
-            fileSequence.eventHandler.listenToEvent("Files Updated", onFilesUpdated); // Only the first sequence is supported right now.
-            viewPort.eventHandler.listenToEvent("Offset Changed", onOffsetChanged);
+            filesUpdatedEventSubscriptionId = fileSequence.eventHandler.listenToEvent("Files Updated", onFilesUpdated);// Only the first sequence is supported right now.
+            offsetChangedEventSubscriptionId = viewPort.eventHandler.listenToEvent("Offset Changed", onOffsetChanged);
 
-            thisObject.container.eventHandler.listenToEvent('Dimmensions Changed', function () {
+            immensionsChangedEventSubscriptionId = thisObject.container.eventHandler.listenToEvent('Dimmensions Changed', function () {
                 recalculate(callBackFunction);
                 recalculateScale(callBackFunction);
             })