Added reference to original C. sativa publication

Author: iimog

docs/index.md

@@ -3,3 +3,8 @@
 This tutorial leads you through the process of loading transcriptomic data into TBro and analyzing it.
 
 ## Cannabis sativa transcriptome
+Original data published in:
+
+Harm van Bakel et al. “The draft genome and transcriptome of Cannabis sativa.”
+In: Genome biology 12.10 (Jan. 2011), R102. issn: 1465-6914. doi: 10.1186/gb-
+2011-12-10-r102. url: http://genomebiology.com/2011/12/10/R102.