1. X.Y. Guo, R. Kleinrahm, W. Wagner, Messung der Gasdichten von verschiedenen Erdgasen im Temperaturbereich von 0°C bis 50°C und Drücken bis 120bar, Final Report for Ruhrgas AG, Lehrstuhl für Thermodynamik, Ruhr-Universität Bochum, Germany, 1990. (available online: ).
2. Results of (pressure, density, temperature) measurements on methane and on nitrogen in the temperature range from 273.15 K to 323.15 K at pressures up to 12 MPa using a new apparatus for accurate gas-density measurements
3. W. Wagner, R. Kleinrahm, X. Y. Guo, G. Olbricht, M. Jaeschke, Experimental investigations of the vos effect on gas density transducers for natural gas pipelines, in: Proceedings of the 1992 International Gas Research Conference, Florida 1992, Government Institutes Inc., Rockville, MD, 1993, pp. 863–874. (Available online: ).
4. Densities and Dew Points of Vapor Mixtures of Methane + Propane and Methane + Propane + Hexane Using a Dual-Sinker Densimeter
5. W. Wagner, R. Kleinrahm, N. Pieperbeck, M. Jaeschke, A new apparatus for high-precision gas-density measurements to calibrate gas-density transducers, in: Proceedings of the 1989 International Gas Research Conference, Tokyo 1989, Government Institutes Inc., Rockville, MD, 1990, pp. 462–471. (Available online: ).