diff --git a/README.md b/README.md
index 61622a8..07bb9ab 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@
 `latexify` is a Python package to compile a fragment of Python source code to a
 corresponding $\LaTeX$ expression:
 
-![Example of latexify usage](example.jpg)
+![Example of latexify usage](https://github.com/google/latexify_py/blob/main/example.jpg)
 
 `latexify` provides the following functionalities:
 
@@ -34,13 +34,17 @@ corresponding $\LaTeX$ expression:
 
 ## Getting started
 
-See the [example notebook](examples/latexify_examples.ipynb), which provides several
+See the
+[example notebook](https://github.com/google/latexify_py/blob/main/examples/latexify_examples.ipynb),
+which provides several
 use-cases of this library.
 
 You can also try the above notebook on
 [Google Colaboratory](https://colab.research.google.com/github/google/latexify_py/blob/main/examples/latexify_examples.ipynb).
 
-See also the official [documentation](docs/index.md) for more details.
+See also the official
+[documentation](https://github.com/google/latexify_py/blob/main/docs/index.md)
+for more details.
 
 ## How to Contribute
 
diff --git a/src/latexify/_version.py b/src/latexify/_version.py
index 5afb350..e4afc2e 100644
--- a/src/latexify/_version.py
+++ b/src/latexify/_version.py
@@ -3,4 +3,5 @@
 DON'T TOUCH THIS FILE.
 This file is replaced during the release process.
 """
+
 __version__ = "0.0.0a0"
diff --git a/src/latexify/frontend.py b/src/latexify/frontend.py
index c2a7875..941b035 100644
--- a/src/latexify/frontend.py
+++ b/src/latexify/frontend.py
@@ -11,15 +11,13 @@
 @overload
 def algorithmic(
     fn: Callable[..., Any], **kwargs: Any
-) -> ipython_wrappers.LatexifiedAlgorithm:
-    ...
+) -> ipython_wrappers.LatexifiedAlgorithm: ...
 
 
 @overload
 def algorithmic(
     **kwargs: Any,
-) -> Callable[[Callable[..., Any]], ipython_wrappers.LatexifiedAlgorithm]:
-    ...
+) -> Callable[[Callable[..., Any]], ipython_wrappers.LatexifiedAlgorithm]: ...
 
 
 def algorithmic(
@@ -55,15 +53,13 @@ def wrapper(f):
 @overload
 def function(
     fn: Callable[..., Any], **kwargs: Any
-) -> ipython_wrappers.LatexifiedFunction:
-    ...
+) -> ipython_wrappers.LatexifiedFunction: ...
 
 
 @overload
 def function(
     **kwargs: Any,
-) -> Callable[[Callable[..., Any]], ipython_wrappers.LatexifiedFunction]:
-    ...
+) -> Callable[[Callable[..., Any]], ipython_wrappers.LatexifiedFunction]: ...
 
 
 def function(
@@ -99,15 +95,13 @@ def wrapper(f):
 @overload
 def expression(
     fn: Callable[..., Any], **kwargs: Any
-) -> ipython_wrappers.LatexifiedFunction:
-    ...
+) -> ipython_wrappers.LatexifiedFunction: ...
 
 
 @overload
 def expression(
     **kwargs: Any,
-) -> Callable[[Callable[..., Any]], ipython_wrappers.LatexifiedFunction]:
-    ...
+) -> Callable[[Callable[..., Any]], ipython_wrappers.LatexifiedFunction]: ...
 
 
 def expression(
diff --git a/src/latexify/ipython_wrappers.py b/src/latexify/ipython_wrappers.py
index c77a869..321a327 100644
--- a/src/latexify/ipython_wrappers.py
+++ b/src/latexify/ipython_wrappers.py
@@ -38,8 +38,7 @@ def __call__(self, *args) -> Any:
         return self._fn(*args)
 
     @abc.abstractmethod
-    def __str__(self) -> str:
-        ...
+    def __str__(self) -> str: ...
 
     @abc.abstractmethod
     def _repr_html_(self) -> str | tuple[str, dict[str, Any]] | None: