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2. Franken S, Müller HS (1999) Investigations on the frost/de-icing resistance of lime mortars. Proceedings of the 5th International WTA-Colloquium on Materials Science and Restoration, Esslingen, Germany, Nov., 2:927–936 (only available in German).
3. Arnold B (1998) Medieval plasters and mortars in the federal state Brandenburg. Arbeitshefte des Brandenburgischen Landesamtes für Denkmalpflege pp. 139–140 (only available in German).
4. Zier H-W, Weise G (1989) Investigations on the determination of the connection between mix proportions, aggregate parameters and compressive strengths of rendering mortars. Betontechnik 10:27–30 (only available in German).
5. Balkowski D (1982) Cracking of rendering mortars applied to ancient surfaces–causes and avoidance. Bausanierung 3:97–100 (only available in German).