@article{Graue2013,
author = "B. Graue and S. Siegesmund and P. Oyhantcabal and R. Naumann and T. Licha and Klaus Simon",
doi = "10.1007/s12665-012-2161-6",
journal = "Environ Earth Sci",
title = "{T}he effect of air pollution on stone decay: the decay of the {D}rachenfels trachyte in industrial, urban, and rural environments---a case study of the {C}ologne, {A}ltenberg and {X}anten cathedrals",
url = "https://doi.org/10.1007/s12665-012-2161-6",
volume = "69",
year = "2013",
}