diff --git a/src/event-handle.js b/src/event-handle.js
index e2c0478..eb7c047 100644
--- a/src/event-handle.js
+++ b/src/event-handle.js
@@ -5,6 +5,24 @@
  * event management and chaining.
  */
 class EventHandle {
+    /**
+     * @type {import('./events.js').Events}
+     * @private
+     */
+    owner;
+
+    /**
+     * @type {string}
+     * @private
+     */
+    name;
+
+    /**
+     * @type {import('./events.js').HandleEvent}
+     * @private
+     */
+    fn;
+
     /**
      * Creates an instance of EventHandle.
      *
@@ -58,4 +76,4 @@ class EventHandle {
     }
 }
 
-export default EventHandle;
+export { EventHandle };
diff --git a/src/events.js b/src/events.js
index ada054b..1bfd2d1 100644
--- a/src/events.js
+++ b/src/events.js
@@ -1,4 +1,4 @@
-import EventHandle from './event-handle.js';
+import { EventHandle } from './event-handle.js';
 
 /**
  * @callback HandleEvent
@@ -269,4 +269,4 @@ class Events {
     }
 }
 
-export default Events;
+export { Events };
diff --git a/src/history.js b/src/history.js
index b6f053a..9117c17 100644
--- a/src/history.js
+++ b/src/history.js
@@ -1,4 +1,4 @@
-import Events from './events.js';
+import { Events } from './events.js';
 
 /**
  * @typedef {object} HistoryAction
@@ -288,4 +288,4 @@ class History extends Events {
     }
 }
 
-export default History;
+export { History };
diff --git a/src/index.js b/src/index.js
index 25e6bf5..fc04635 100644
--- a/src/index.js
+++ b/src/index.js
@@ -8,12 +8,12 @@
  * @module Observer
  */
 
-import EventHandle from './event-handle.js';
-import Events from './events.js';
-import History from './history.js';
-import Observer from './observer.js';
-import ObserverHistory from './observer-history.js';
-import ObserverList from './observer-list.js';
+import { EventHandle } from './event-handle.js';
+import { Events } from './events.js';
+import { History } from './history.js';
+import { Observer } from './observer.js';
+import { ObserverHistory } from './observer-history.js';
+import { ObserverList } from './observer-list.js';
 
 export {
     EventHandle,
diff --git a/src/observer-history.js b/src/observer-history.js
index 672eadd..fc7fde8 100644
--- a/src/observer-history.js
+++ b/src/observer-history.js
@@ -1,5 +1,5 @@
-import Events from './events.js';
-import Observer from './observer.js';
+import { Events } from './events.js';
+import { Observer } from './observer.js';
 
 /**
  * History for an observer.
@@ -240,4 +240,4 @@ class ObserverHistory extends Events {
     }
 }
 
-export default ObserverHistory;
+export { ObserverHistory };
diff --git a/src/observer-list.js b/src/observer-list.js
index 332e76d..0820c80 100644
--- a/src/observer-list.js
+++ b/src/observer-list.js
@@ -1,5 +1,5 @@
-import Events from './events.js';
-import Observer from './observer.js';
+import { Events } from './events.js';
+import { Observer } from './observer.js';
 
 /**
  * A list of observers.
@@ -300,4 +300,4 @@ class ObserverList extends Events {
     }
 }
 
-export default ObserverList;
+export { ObserverList };
diff --git a/src/observer.js b/src/observer.js
index 99d0288..39e073a 100644
--- a/src/observer.js
+++ b/src/observer.js
@@ -1,4 +1,4 @@
-import Events from './events.js';
+import { Events } from './events.js';
 import { arrayEquals } from './utils.js';
 
 /**
@@ -986,4 +986,4 @@ class Observer extends Events {
     }
 }
 
-export default Observer;
+export { Observer };