@misc{indiciaee1d26938da71,
  title = {Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory-Determination of methylene blue active substances by spectrophotometry},
  author = {Mark R. Burkhardt and Pete J. Cinotto and Galen W. Frahm and Mark T. Woodworth and Jeffrey W. Pritt},
  year = {1995},
  doi = {10.3133/ofr95189},
  url = {https://pubs.usgs.gov/publication/ofr95189},
  note = {Source identifier: ofr95189}
}