Towards black-box calculations of tunneling splittings obtained from vibrational structure methods based on normal coordinates. Spectrochim. Acta - Part A Mol. Biomol. Spectrosc., (119):100–106, February 2014. [PUMA: chemie ion,Normal from:alexanderdenzel coordinates,Tunneling rauhut Ammonia,Hydronium calculations splittings,VCI theoretische stuttgart theochem] URL