Reference Label	Details
Martin 1996	J. M. L. Martin and T. J. Lee, Chem. Phys. Lett. 258, 129-135 (1996) Accurate ab initio Quartic Force Field and Vibrational Frequencies of the NH4+ Ion and its Deuterated Forms
Martin 1996a	J. M. L. Martin and T. J. Lee, Chem. Phys. Lett. 258, 136-143 (1996) The Atomization Energy and Proton Affinity of NH3. An ab initio Calibration Study