diff --git a/documents/Makefile b/documents/Makefile
index f1af5ba..b2a1182 100644
--- a/documents/Makefile
+++ b/documents/Makefile
@@ -8,6 +8,10 @@ HTML_FILES := $(patsubst %.lyx,%.html,$(LYX_FILES))
 TARGET_FILES := $(foreach file,$(LYX_FILES),_output/$(basename $(notdir $(file))).html)
 # menue and footer files
 ASC_FILES := $(wildcard *.asc)
+# png files (get converted to eps)
+PNG_FILES := $(shell find -name *.png)
+# converted eps files
+EPS_FILES := $(patsubst %.png,%.eps,$(PNG_FILES))
 # look for lyx executable
 LYX_BIN = $(shell which lyx lyx-qt lyx-xform | head -1)
 
@@ -57,7 +61,7 @@ $(HTML_FILES): %.html: %.tex
 	rm $(dir $@)/menue.inc
 	# die html-Datei wurde jetzt im _output-Verzeichnis erstellt (inklusive Bilder)
 	-rm _output/WARNINGS $*-labels.pl $*-internals.pl $*.log 2>/dev/null
-	-rm _output/$(dir $@).css 2>/dev/null
+	-rm _output/$(notdir $(basename $@)).css 2>/dev/null
 	-rm _output/images.aux _output/images.log _output/images.out _output/images.pl _output/images.text _output/img?.old _output/labels.pl _output/missfont.log _output/images.tex 2>/dev/null
 	mv _output/$(notdir $(basename $@)).html $@
 	python mod_html_files.py $@
@@ -68,6 +72,7 @@ $(HTML_FILES): %.html: %.tex
 clean:
 	-rm $(TEX_FILES) 2>/dev/null
 	-rm $(HTML_FILES) 2>/dev/null
+	-rm $(EPS_FILES) 2>/dev/null
 	-rm -r _output 2>/dev/null
 #	-rm $(foreach dir,$(DOCUMENT_NAMES),$(dir)/menue.inc) 2>/dev/null
 #	-rm $(foreach dir,$(DOCUMENT_NAMES),$(dir)/WARNINGS) 2>/dev/null