diff --git a/ckipnlp/__init__.py b/ckipnlp/__init__.py
index 5618a5a..e863155 100644
--- a/ckipnlp/__init__.py
+++ b/ckipnlp/__init__.py
@@ -10,7 +10,7 @@
 __copyright__ = '2018-2020 CKIP Lab'
 
 __title__ = 'CKIPNLP'
-__version__ = '0.8.4'
+__version__ = '0.8.5'
 __description__ = 'CKIP CoreNLP'
 __license__ = 'CC BY-NC-SA 4.0'
 
diff --git a/ckipnlp/container/coref.py b/ckipnlp/container/coref.py
index 87ba004..5c3f1d9 100644
--- a/ckipnlp/container/coref.py
+++ b/ckipnlp/container/coref.py
@@ -52,7 +52,7 @@ class CorefToken(_BaseTuple, _CorefToken):
     .. admonition:: Data Structure Examples
 
         Text format
-            Used for :meth:`to_list`.
+            Used for :meth:`to_text`.
 
             .. code-block:: python
 
@@ -94,7 +94,7 @@ class CorefSentence(_BaseSentence):
     .. admonition:: Data Structure Examples
 
         Text format
-            Used for :meth:`to_list`.
+            Used for :meth:`to_text`.
 
             .. code-block:: python
 
@@ -138,7 +138,7 @@ class CorefParagraph(_BaseList):
     .. admonition:: Data Structure Examples
 
         Text format
-            Used for :meth:`to_list`.
+            Used for :meth:`to_text`.
 
             .. code-block:: python
 
diff --git a/docs/conf.py b/docs/conf.py
index 2c91348..bd1eb4e 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -39,7 +39,6 @@
 # ones.
 extensions = [
     'sphinx.ext.autodoc',
-    'sphinx.ext.imgconverter',
     'sphinx.ext.napoleon',
     'sphinx.ext.viewcode',
     'sphinx_rtd_theme',