Cita APA

Smith, R. A., Alexander, R. B., & Schwarz, G. E. Natural background concentrations of nutrients in streams and rivers of the conterminous United States.

Chicago Style Citation

Smith, Richard A., Richard B. Alexander, i Gregory E. Schwarz. Natural Background Concentrations of Nutrients in Streams and Rivers of the Conterminous United States.

Cita MLA

Smith, Richard A., Richard B. Alexander, i Gregory E. Schwarz. Natural Background Concentrations of Nutrients in Streams and Rivers of the Conterminous United States.