Long-term in situ non-invasive spectroscopic monitoring of weathering processes in open-air prehistoric rock art sites

1. Aramendia, J.
2. de Vallejuelo, S.F.-O.
3. Maguregui, M.
4. Martinez-Arkarazo, I.
5. Giakoumaki, A.
6. Martí, A.P.
7. Madariaga, J.M.
8. Ruiz, J.F.