1. Market Size of the Global Health Club Industry from 2009 to 2013 (In Billion U.S. Dollars)*;IHRSA,2014
2. Thermal Environmental Conditions for Human Occupancy;ANSI/ASHRAE/IES Standard 55-2013,2013
3. Ergonomics of the Thermal Environment–analytical Determination and Interpretation of Thermal Comfort Using Calculation of the PMV and PPD Indices and Local Thermal Comfort Criteria;ISO7730-2005,2005
4. ACSM's Health/Fitness Facility Standards and Guidelines-4th Edition;American College of Sports Medicine,2012
5. International Fitness Association, Gym Temperature and Noise Limits. http://www.ifafitness.com/health/temperature.htm, last visited on April 8, 2014.