Comparing illicit drug use in 19 European cities through sewage analysis
Thomas, K. V., Bijlsma, L., Castiglioni, S., Covaci, A., Emke, E., Grabic, R., Hernández, F., Karolak, S., Kasprzyk-Hordern, B., Lindberg, R. H., Lopez de Alda, M., Meierjohann, A., Ort, C., Pico, Y., Quintana, J. B., Reid, M., Rieckermann, J., Terzic, S., van Nuijs, A. L. N. & de Voogt.
Science of The Total Environment, Volume 432, 15 August 2012, Pages 432-439