1. Acoustics - Attenuation of sound during propagation outdoors - Part 2: General method of calculation, International Standard ISO 9613-2: 2000, International Organization for Standardization, Geneva, Switzerland, (1990).
2. Acoustics - Description, measurement and assessment of environmental noise - Part 1: Basic quantities and assessment procedures, International Standard ISO 9613-1: 2003, (1990), International Organization for Standardization, Geneva, Switzerland.
3. Non-parametric methods of estimation of type A uncertainty of the environmental noise hazard indices;W. Batko;Archives of Acoustics,2009
4. A linear-time component-labeling algorithm using contour tracing technique;F. Chang;Journal of CVIU,2004