A Vibrating Plate Fabricated by the Methods of Microelectromechanical Systems (MEMS) for the Simultaneous Measurement of Density and Viscosity: Results for Argon at Temperatures Between 323 and 423 K at Pressures up to 68 MPa Goodwin, A.R.H.; Fitt, A.D.; Ronaldson, K.A.; Wakeham, W.A.; International Journal of Thermophysics 2006, 27, 1650-1676