1. Memoire sur les gisements de manganèse en Italie;Burkhardt,1956
2. Mining and beneficiation problems related to the manganese deposits in Northern Latium;Massacci,1979
3. Extraction of manganese from a low grade ore of Latium by reducing leaching;Abbruzzese;Boll. Assoc. Miner. Subalpina,1980
4. Recent research on leaching manganese;Chamberlain,1982
5. Leaching of domestic manganese with dissolved SO2;Pahlman,1984