diff --git a/Makefile b/Makefile
index 262b44e..2850954 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,6 @@ LATEX=pdflatex
 
 .PHONY: pdf
 pdf:
-	printf '\\renewcommand{\\docversion}{Version %s}' "$$(git describe --tags --abbrev=6)" |tee sietch.ver
 	# If $(LATEX) fails, touch an input so that 'make' won't think it is up-to-date next time.
 	rm -f sietch.aux sietch.bbl sietch.blg sietch.brf sietch.bcf
 	$(LATEX) sietch.tex
@@ -16,6 +15,17 @@ pdf:
 	dot -Tpdf -o itm-zchain.pdf itm-zchain.gv # && evince itm-zchain.pdf
 	evince sietch.pdf
 
+ru:
+	# If $(LATEX) fails, touch an input so that 'make' won't think it is up-to-date next time.
+	rm -f sietch_ru.aux sietch_ru.bbl sietch_ru.blg sietch_ru.brf sietch_ru.bcf
+	$(LATEX) sietch_ru.tex
+	biber sietch_ru
+	$(LATEX) sietch_ru.tex
+	$(LATEX) sietch_ru.tex
+	$(LATEX) sietch_ru.tex
+	dot -Tpdf -o itm-zchain.pdf itm-zchain.gv
+
 .PHONY: clean
 clean:
-	rm -f sietch.dvi sietch.pdf sietch.bbl sietch.blg sietch.brf sietch.toc sietch.aux sietch.out sietch.log sietch.bcf sietch.run.xml sietch.ver
+	rm -f sietch.dvi sietch.pdf sietch.bbl sietch.blg sietch.brf sietch.toc sietch.aux sietch.out sietch.log sietch.bcf sietch.run.xml
+	rm -f sietch_ru.dvi sietch_ru.pdf sietch_ru.bbl sietch_ru.blg sietch_ru.brf sietch_ru.toc sietch_ru.aux sietch_ru.out sietch_ru.log sietch_ru.bcf sietch_ru.run.xml
diff --git a/itm-zchain.pdf b/itm-zchain.pdf
index 236af98..cefdf6e 100644
Binary files a/itm-zchain.pdf and b/itm-zchain.pdf differ
diff --git a/sietch.pdf b/sietch.pdf
deleted file mode 100644
index 93226be..0000000
Binary files a/sietch.pdf and /dev/null differ