diff --git a/AstConv/HtmlStruct.fs b/AstConv/HtmlStruct.fs
index 79c46be..6228dca 100644
--- a/AstConv/HtmlStruct.fs
+++ b/AstConv/HtmlStruct.fs
@@ -63,8 +63,8 @@ open System
 
                 interface IContainer with
                     member this.children(): IDomUnit list = childs
-                    member this.append(childs: IDomUnit list): IContainer =
-                        raise (System.NotImplementedException())
+                    member this.append(new_list: IDomUnit list): IContainer =
+                        VolumePage(page_hrefs, volume, childs@new_list)
             end
 
         type StoryPage(page_hrefs: string, story: IDomUnit, childs: IDomUnit list) =
@@ -81,8 +81,8 @@ open System
 
                 interface IContainer with
                     member this.children(): IDomUnit list = childs
-                    member this.append(childs: IDomUnit list): IContainer =
-                        raise (System.NotImplementedException())
+                    member this.append(list: IDomUnit list): IContainer =
+                        StoryPage(page_hrefs, story, childs@list)
             end
 
         type PointPage(page_hrefs: string, point: IDomUnit, refer_list: IDomUnit list) =
diff --git a/AstConv/Program.fs b/AstConv/Program.fs
index bc159f4..e6ac7f9 100644
--- a/AstConv/Program.fs
+++ b/AstConv/Program.fs
@@ -17,7 +17,7 @@ entry.visitWith(visitor) |> ignore
 
 let volume_pages = volume_page_assemble(visitor.contents()) |> List.map<VolumePage, IDomUnit> (fun x->x)
 let story_pages = story_page_assemble(visitor.contents())  |> List.map<StoryPage, IDomUnit> (fun x->x)
-let refers = point_page_assemble(volume_pages @ story_pages)
+let point_pages = point_page_assemble(volume_pages @ story_pages)
 
-for refs in refers do
+for refs in point_pages do
     System.Console.WriteLine(refs.ToString())
\ No newline at end of file