diff --git a/Makefile b/Makefile
index b92a88977..0b0fd61fe 100644
--- a/Makefile
+++ b/Makefile
@@ -21,11 +21,11 @@ clean:
 
 # generate documentation
 docs: develop
-	find doc/en -name '*.txt' -not -path 'doc/en/_build/*' | xargs .env/bin/regendoc ${REGENDOC_ARGS}
+	find doc/en -name '*.rst' -not -path 'doc/en/_build/*' | xargs .env/bin/regendoc ${REGENDOC_ARGS}
 	cd doc/en; make html
 
 # upload documentation
 upload-docs: develop
-	find doc/en -name '*.txt' -not -path 'doc/en/_build/*' | xargs .env/bin/regendoc ${REGENDOC_ARGS} --update
+	find doc/en -name '*.rst' -not -path 'doc/en/_build/*' | xargs .env/bin/regendoc ${REGENDOC_ARGS} --update
 	#cd doc/en; make install
 
diff --git a/doc/en/Makefile b/doc/en/Makefile
index ce62f0ce6..e54b6b09a 100644
--- a/doc/en/Makefile
+++ b/doc/en/Makefile
@@ -46,7 +46,7 @@ installall: clean install installpdf
 	@echo "done"
 
 regen:
-	PYTHONDONTWRITEBYTECODE=1 COLUMNS=76 regendoc --update *.txt */*.txt
+	PYTHONDONTWRITEBYTECODE=1 COLUMNS=76 regendoc --update *.rst */*.rst
 
 html:
 	$(SPHINXBUILD) -b html $(ALLSPHINXOPTS) $(BUILDDIR)/html