1. ISO 5136, 1990, International Organisation for Standardization, Geneva, Switzerland, International Standard, Acoustics—determination of sound power radiated into a duct by fans—in-duct method
2. ISO/DIS 5136, 1999, International Organisation for Standardization, Geneva, Switzerland, Layout for a Draft International Standard, Determination of sound power radiated into a duct by fans and other air moving devices—in-duct method
3. ISO/DIS 5136, 1977, International Organisation for Standardization, Geneva, Switzerland, Draft International Standard, Acoustics—determination of sound power radiated into a duct by fans—in-duct method
4. ISO/DIS 5136.2, 1985, International Organisation for Standardization, Geneva, Switzerland, Draft International Standard, Acoustics—Determination of sound power radiated into a duct by fans—in-duct method
5. EN 25136, 1993, European Committee for Standardization, European Standard, Acoustics—determination of sound power radiated into a duct by fans—in-duct method