Compliance Recertification Application 2014 
      
      Wall, N.A., and S.A. Mathews.
      
         - Wall, N.A., and S.A. Mathews. 2005. "Sustainability of Humic Acids in the Presence of Magnesium Oxide." Applied Geochemistry, vol. 20: 1704–13. (Unavailable)
(*Indicates a reference that has not been previously submitted.)