Pearson, J., Wells, D. M., Seller, K. J., Bennett, A., Soares, A., Woodall, J., & Ingrouille, M. J. (2000). Traffic exposure increases natural 15N and heavy metal concentrations in mosses. New Phytologist, 147(2), 317-326. https://doi.org/10.1046/j.1469-8137.2000.00702.x