1. Aires-Barros, L., Alves, L. M., Carmo, A. M. M., Graça, R. C., Mauricio, A. S., & Ribeiro, M. I. M. (1990). Weathering and air pollution action on limestones of Jeronimos Monastery, Lisbon. C.E.C. Contact Group “Air Pollution Effects on Historics Monuments”, Seville 9–13 May 1990.
2. Allen, A. G., Nemitz, E., Shi, J. P., Harrison, R. M., & Greenwood, J. C. (2001). Size distribution of the trace metals in atmospheric aerosols in the UK. Atmospheric Environment, 35, 4581–4591. doi: 10.1016/S1352-2310(01)00190-X .
3. Artiñano, B., Querol, X., Salvador, P., Rodríguez, S., Alonso, D. G., & Alastuey, A. (2001). Assessment of airborne particulate levels in Spain in relation to the new EU-directive. Atmospheric Environment, 34, 543–553.
4. Boix, A., Jordán, M. M., Querol, X., & Sanfeliu, T. (2001). Characterisation of total suspended particles around a power station in an urban coastal area in eastern Spain. Environmental Geology, 40, 891–896. doi: 10.1007/s002540100249 .
5. Camuffo, D., Del Monte, M., Sabbioni, C., & Vittori, O. (1982). Wetting, deterioration and visual features of stone surfaces in an urban area. Atmospheric Environment, 16, 2253–2259. doi: 10.1016/0004-6981(82)90296-7 .