Bull, I. D. (1997). New molecular methods for tracing natural and anthropogenic inputs to soils and sediments. University of Bristol.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रBull, Ian David. New Molecular Methods for Tracing Natural and Anthropogenic Inputs to Soils and Sediments. England: University of Bristol, 1997.
एमएलए (8वां संस्करण) प्रशस्ति पत्रBull, Ian David. New Molecular Methods for Tracing Natural and Anthropogenic Inputs to Soils and Sediments. University of Bristol, 1997.
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