diff --git a/Treemmer.py b/Treemmer.py
index 8fb9eb8648f8c8352188226ee886104e11621f87..8db26d388749f7136e714a67eb73b55125b710f8 100644
--- a/Treemmer.py
+++ b/Treemmer.py
@@ -20,7 +20,8 @@
 # You have to install ete3 http://etetoolkit.org/
 # and joblib https://pythonhosted.org/joblib/ to run Treemmer
 
-
+# If you use Treemmer for your research, please cite:
+# Treemmer: a tool to reduce large phylogenetic datasets with minimal loss of diversity. Menardo et. al (2018), BMC Bioinformatics (in press).
 
 from collections import defaultdict
 from joblib import Parallel, delayed
@@ -418,7 +419,8 @@ if (arguments.list_meta):
 if (arguments.list_meta_count):
 	dict_meta_count = read_list_tags(arguments.list_meta_count)
 
-if arguments.verbose > 0:													# print progress on standard output
+if arguments.verbose > 0:
+												# print progress on standard output
 	print "N of taxa in tree is : "+ str(len(t))
 	
 	if arguments.solve_polytomies:
@@ -586,5 +588,6 @@ if ((stop == 0) or (arguments.plot_always)):														# create file for plot
 	if not arguments.no_plot:
 		make_plot()
 
-
+if (arguments.verbose > 0):
+	print "\n If you use Treemmer for your research, please cite:\n\n \"Treemmer: a tool to reduce large phylogenetic datasets with minimal loss of diversity\" Menardo et. al (2018), BMC Bioinformatics (in press)\n\n"