PERUMIN 33 Mining Convention, e leng e 'ngoe ea liketsahalo tsa bohlokoa ka ho fetisisa tsa merafo lefatšeng.Batsamaisi ba rona ba thekiso ba ile ba ea lipontšong tsa khoebo ka Loetse 18-22 2017 Univesithing ea Sechaba ea San Agustin(Arequipa)