1. Akbar, K. F., Hale, W. H. G., Headly, A. D., & Athar, M. (2006). Heavy metal contamination of roadside soils of Northern England. Soil & Water Research, 1(4), 168–163.
2. Al-Chalabi, A. S., & Hawker, D. (2000). Distribution of vehicular lead in roadside soils of major roads of Brisbane, Australia. Water, Air and Soil Pollution, 118, 299–310.
3. Chen, T. B., Wong, J. W. C., Zhou, H. Y., & Wong, H. Y. (1997). Assessment of trace metal distribution and contamination in surface soils of Hong Kong. Environmental Pollution, 96, 61–68.
4. Davis, J. C. (1973). Statistics and data analysis in Geology. London: Wiley.
5. Donaldson, A., & Bennett, A. (2004). Ecological effects of roads: Implications for the internal fragmentation of Australian Parks and Reserves. Deakin University.