Observations of Titan's stratosphere during northern summer: temperatures, CH3CN and CH3D abundances by Thelen, AE, Nixon, CA, Cordiner, MA, Lellouch, E, Vinatier, S, Teanby, NA, Butler, B, Charnley, SB, Cosentino, RG, de Kleer, K, Irwin, PGJ, Gurwell, MA, Kisiel, Z, Moreno, R