diff --git a/Makefile b/Makefile
index 161e4c1..473b793 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-# Copyright (c) 2011-2014 Casper Ti. Vector
+# Copyright (c) 2011-2014,2019 Casper Ti. Vector
 # Public domain.
 
 TITLE = pkuthss
@@ -11,9 +11,6 @@ default: dist
 qa:
 	utils/qa
 
-toutf8 togbk:
-	utils/enc $@
-
 bump:
 	utils/bump VERSION=$(VERSION)
 
diff --git a/utils/enc b/utils/enc
deleted file mode 100755
index 69570e2..0000000
--- a/utils/enc
+++ /dev/null
@@ -1,22 +0,0 @@
-#!/usr/bin/make -f
-#
-# Copyright (c) 2011-2014 Casper Ti. Vector
-# Public domain.
-
-FIND_GBKCRLF = -name '*.bat*'
-TOUTF8 = enca -L zh -x UTF-8
-TOGBK = enca -L zh -x GBK
-
-toutf8:
-	find doc/example -not $(FIND_GBKCRLF) -type f -exec $(TOUTF8) '{}' '+'
-	sed -i -e '/\\documentclass/ s/GBK/UTF8/' \
-		-e '/^\\usepackage.*{biblatex}$$/ s/gbk/utf8/' \
-		doc/example/thesis.tex
-
-togbk:
-	find doc/example -not $(FIND_GBKCRLF) -type f -exec $(TOGBK) '{}' '+'
-	sed -i -e '/\\documentclass/ s/UTF8/GBK/' \
-		-e '/^\\usepackage.*{biblatex}$$/ s/utf8/gbk/' \
-		doc/example/thesis.tex
-
-# vim:ts=4:sw=4