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Methods of Soil Resampling to Monitor Changes in the Chemical Concentrations of Forest Soils
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Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa

A C Crampin1, V Mwinuka, S S Malema

  • 1London School of Hygiene and Tropical Medicine, Keppel St, London WC1E 7HT, UK.

Transactions of the Royal Society of Tropical Medicine and Hygiene
|November 15, 2001
PubMed

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