Sart-Xhoffraix. Carte géologique de Wallonie. 50/1-2. Notice explicative ; Sart-Xhoffraix. Geological of Wallonia (Belgium). 50/1-2. Leaflet

Manuscript of the leaflet of the new geological map of Wallonia that will be published at the scale of 1/25.000, based on a new field work and using previous scientific data produced, since the first edition* published in 1899 (Gustave Dewalque) at the scale of 1/40,000 by the "Commission Géologique de Belgique" (*a map of which part of the territory belonged to Prussia and was not covered by the 1890-1920 mapping program). ; Révision et seconde édition (1ère édition complète) ; Programme de révision de la carte géologique de Wallonie. Recherches collectives d'intérêt général.