1. CNNMoney.com (2015). Crazy money – Airbnb valued at over $25 billion.
http://money.cnn.com/2015/06/27/technology/airbnb-funding-valuation-update/
, Retrieved 27 June 2015.
2. Eye for Travel (2015). Heavy weight travel distribution title fight – Round II.
http://www.hotelnewsresource.com/article83598.html
, Retrieved 14 May 2015.
3. J. D. Power (2015). Hotel loyalty rewards program satisfaction report.
http://www.jdpower.com/press-releases/2015-hotel-loyaltyrewards-program-satisfaction-report
, Retrieved 8 April 2015.