diff --git a/lib/smartfm/models/list.rb b/lib/smartfm/models/list.rb
index 105c586..635fb38 100644
--- a/lib/smartfm/models/list.rb
+++ b/lib/smartfm/models/list.rb
@@ -1,6 +1,6 @@
 class Smartfm::List < Smartfm::Base
   ATTRIBUTES = [:id, :title, :description, :icon, :square_icon, :item_count, :user_count, :iknow, :dictation, :brainspeed,
-                :language, :translation_language, :list_type, :transcript, :embed, :tags, :media_entry,
+                :language, :translation_language, :item_type, :transcript, :embed, :tags, :media_entry,
                 :attribution_license_id, :items, :sentences, :user]
   READONLY_ATTRIBUTES = [:id, :icon, :item_count, :user_count, :iknow, :dictation, :brainspeed, :user]
   attr_accessor *(ATTRIBUTES - READONLY_ATTRIBUTES)
@@ -50,7 +50,7 @@ def initialize(params = {})
       @dictation  = Application.new(common_settings.merge(:dictation  => params[:dictation]))
       @brainspeed = Application.new(common_settings.merge(:brainspeed => params[:brainspeed]))
     end
-    @list_type   = params[:list_type]   # for list creation
+    @item_type   = params[:item_type]   # for list creation
     @transcript  = params[:transcript]  # for list creation
     @embed       = params[:embed]       # for list creation
     @tags        = params[:tags]        # for list creation
@@ -90,10 +90,7 @@ def to_post_data
       'list[translation_language]' => self.translation_language || 'ja'
     }
     # Optional attributes
-    if self.list_type
-      post_data['list[type]'] = self.list_type
-    end
-    [:transcript, :embed, :tags, :media_entry, :author, :author_url, :attribution_license_id ].each do |key|
+    [:transcript, :embed, :tags, :item_type].each do |key|
       if self.send("#{key}")
         post_data["list[#{key}]"] = self.send("#{key}")
       end
diff --git a/lib/smartfm/models/notification.rb b/lib/smartfm/models/notification.rb
index 63b545d..8d7b3a9 100644
--- a/lib/smartfm/models/notification.rb
+++ b/lib/smartfm/models/notification.rb
@@ -17,7 +17,7 @@ def initialize(params)
     @context   = params[:context]
   end
 
-  private
+  protected
 
   def to_post_data
     {:message => self.message}
diff --git a/lib/smartfm/modules/acts_as_likable.rb b/lib/smartfm/modules/acts_as_likable.rb
index 1043d1c..748f41c 100644
--- a/lib/smartfm/modules/acts_as_likable.rb
+++ b/lib/smartfm/modules/acts_as_likable.rb
@@ -5,11 +5,11 @@ def likes(params = {})
     self.deserialize(hash, :as => Smartfm::Like) || []
   end
 
-  def like!(auth, params)
+  def like!(auth, params = {})
     self.rest_client.like!(auth, params.merge(:id => self.id))
   end
 
-  def unlike!(auth, params)
+  def unlike!(auth, params = {})
     self.rest_client.unlike!(auth, params.merge(:id => self.id))
   end
 
diff --git a/lib/smartfm/modules/private_content.rb b/lib/smartfm/modules/private_content.rb
index 139bfae..bdcfae3 100644
--- a/lib/smartfm/modules/private_content.rb
+++ b/lib/smartfm/modules/private_content.rb
@@ -12,13 +12,21 @@ def of_current(auth, params = {})
     end
 
     def create(auth, params = {})
-      self.new(params).save
+      self.new(params).save(auth)
     end
   end
 
   module InstanceMethods
     def save(auth)
-      self.rest_client.create(auth, self.to_post_data)
+      result = self.rest_client.create(auth, self.to_post_data)
+      case result
+      when Hash
+        self.deserialize(result)
+      when String
+        self.find(result)
+      else
+        true
+      end
     end
   end
 
diff --git a/lib/smartfm/modules/public_content.rb b/lib/smartfm/modules/public_content.rb
index cf08873..38c93d7 100644
--- a/lib/smartfm/modules/public_content.rb
+++ b/lib/smartfm/modules/public_content.rb
@@ -34,12 +34,15 @@ def delete(obj_id)
 
   module InstanceMethods
     def save(auth)
-      begin
-        obj_id = self.rest_client.create(auth, self.to_post_data)
-      rescue
-        return false
+      result = self.rest_client.create(auth, self.to_post_data)
+      case result
+      when Hash
+        self.deserialize(result)
+      when String
+        self.find(result)
+      else
+        true
       end
-      self.find(obj_id)
     end
 
     def delete(auth)
diff --git a/lib/smartfm/rest_clients/base.rb b/lib/smartfm/rest_clients/base.rb
index 93cd72d..3beeabc 100644
--- a/lib/smartfm/rest_clients/base.rb
+++ b/lib/smartfm/rest_clients/base.rb
@@ -147,18 +147,18 @@ def self.http_get_with_auth(auth, path, params = {})
     case auth.mode
     when :oauth
       response = auth.auth_token.get(path, http_header)
-      handle_rest_response(response, :text)
+      handle_rest_response(response, :json)
     when :basic_auth
       http_connect do
         get_req = Net::HTTP::Get.new(path, http_header)
         get_req.basic_auth(auth.account.username, auth.account.password)
-        [get_req, :text]
+        [get_req, :json]
       end
     end
   end
 
   def self.http_post(auth, path, params = {})
-    self.api_key_required
+    api_key_required
     params.merge!(:api_key => self.config.api_key)
     case auth.mode
     when :oauth
@@ -175,7 +175,7 @@ def self.http_post(auth, path, params = {})
   end
 
   def self.http_delete(auth, path, params = {})
-    self.api_key_required
+    api_key_required
     params.merge!(:api_key => self.config.api_key)
     path = "#{path}?#{params.to_http_str}"
     case auth.mode