Source: https://www.researchgate.net/profile/B-Baghdad-2/publication/342216038_Degradation_et_caracterisation_des_pierres_greseuses_des_monuments_historiques_de_la_ville_d'Ouezzane_Maroc_Degradation_and_characterization_of_sandstone_rocks_of_historical_monuments_in_Ouezzane_city/links/5ee92443458515814a651a7e/Degradation-et-caracterisation-des-pierres-greseuses-des-monuments-historiques-de-la-ville-dOuezzane-Maroc-Degradation-and-characterization-of-sandstone-rocks-of-historical-monuments-in-Ouezzane-city.pdf