1any Weber. Marketing to the Social Web: How Digi%aJ Customer Communities Build Your Business. John Wiley &, Sons,2007(1):25.
2Stanley Milgram. The Small World Problem. Psychology Today, 1967(2):60.
3Jason Schwsrtz.The End Of The Soci&l Network Er&, The Eise Of The Soci&l Circle Er&[EB/OL]. http://www, businessinsider, com/the-end-of-the-soci&l- network-er&-the-rise-of-the-sod&l-cirde-er&-2011 -5/2014-12-24.