1. International Standards Organization ISO/TC43/SC1/WG3. Sound measurement procedure for air moving devices connected to either a discharge duct or an inlet duct.
2. Analysis of the relations between acoustic and aerodynamic parameters for a series of dimensionally similar centrifugal fan rotors;Weidemann;DFVLR Report DLR-FB 71-12,1971
3. Noise from air conditioning fans;Allen;Noise Control,1957
4. How to estimate fan noise;Graham;Sound and Vibration,1982