Smith, R. A., Alexander, R. B., & Schwarz, G. E. Natural background concentrations of nutrients in streams and rivers of the conterminous United States.
Παραπομπή Chicago StyleSmith, Richard A., Richard B. Alexander, και Gregory E. Schwarz. Natural Background Concentrations of Nutrients in Streams and Rivers of the Conterminous United States.
Παραπομπή MLASmith, Richard A., Richard B. Alexander, και Gregory E. Schwarz. Natural Background Concentrations of Nutrients in Streams and Rivers of the Conterminous United States.
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