--- a/LINKS	Sat Jun 03 23:57:07 2017 +0100
+++ b/LINKS	Thu Jun 29 16:48:10 2017 +0100
@@ -30,4 +30,5 @@
 
 
 blockchain
-https://medium.com/@lhartikk/a-blockchain-in-200-lines-of-code-963cc1cc0e54
\ No newline at end of file
+https://medium.com/@lhartikk/a-blockchain-in-200-lines-of-code-963cc1cc0e54
+http://www.samlewis.me/2017/06/a-peek-under-bitcoins-hood/
\ No newline at end of file