1. ANSI S12.60, 2002. American National Standard—acoustical performance criteria, design requirements, and guidelines for schools, 2002.
2. Brazilian Association for Standardization NBR 12179, 1992. Acoustic comfort in closed rooms (in Portuguese).
3. Building Bulletin 93, 2003. United Kingdom. 〈www.teachernet.gov.uk/_doc/5649/ACF12DC.pdf〉.
4. Handbuch der Bauphysik. 7. völlig neubearbeitete Auflage;Bobran,1995
5. Brüel and Kjaer, 2003. Measurements in Building Acoustics. 〈http://www.bk.dk〉.