Maffe - Grandhan. Carte géologique de Wallonie à l'échelle 1:25.000. 54/3-4. Notice explicative ; Maffe - Grandhan. Geological map of Wallonia at the scale 1:25.000. 54/3-4. Leaflet

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition of Lohest and Mourlon, published in 1900 at the scale of 1/40.000 by the "Commission Géologique de Belgique". ; Révision de la carte géologique de la Wallonie