diff --git a/doc/paper/taler.bib b/doc/paper/taler.bib
index ce5b1cb11..74d3ebc95 100644
--- a/doc/paper/taler.bib
+++ b/doc/paper/taler.bib
@@ -48,6 +48,15 @@
   organization={IEEE}
 }
 
+
+@book{ engels1844,
+  author = 	 "Friedrich Engels",
+  title = 	 "{Umrisse zu einer Kritik der Nationalökonomie}",
+  year = 	 "1844",
+  publisher = "Ruge and Marx, Paris",
+}
+
+
 @inproceedings{selby2004analyzing,
   title={Analyzing the Success and Failure of Recent e-Payment Schemes},
   author={Selby, Jack R},
@@ -91,4 +100,3 @@
   www_pdf_url = {https://www.torproject.org/svn/trunk/doc/design-paper/tor-design.pdf},
   www_section = {Anonymous communication},
 }
-