diff --git a/MANIFEST.in b/MANIFEST.in
index f82558f..ac7b6d9 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -2,6 +2,6 @@ include pyopenjtalk/version.py
 exclude .gitignore .gitmodules .travis.yml release.sh tox.ini
 prune .github/*
 prune docs/**
-recursive-include lib *.cpp *.c *.h README LICENSE COPYING CMakeLists.txt *.in
+recursive-include lib *.cpp *.c *.h README COPYING CMakeLists.txt *.in
 exclude lib/open_jtalk/src/mecab/src/config.h
 prune lib/open_jtalk/src/build/**
diff --git a/pyproject.toml b/pyproject.toml
index fe0e1fe..d56bac5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -67,8 +67,8 @@ dev = [
 test = ["pytest", "scipy"]
 marine = ["marine>=0.0.5"]
 
-[tool.setuptools.packages]
-find.namespaces = false
+[tool.setuptools.packages.find]
+include = ["pyopenjtalk*"]
 
 [tool.setuptools.exclude-package-data]
 "*" = ["*.pyx", "*.pxd"]