TY - JOUR AU - Jon Hougen C2 - Journal of Molecular Spectroscopy DA - 1997-01-01 LA - en M1 - 181 PB - Journal of Molecular Spectroscopy PY - 1997 TI - Coordinates, Hamiltonian, and Symmetry Operations for the Small-Amplitude Vibrational Problem in Methyl-Top Internal-Rotor Molecules like CH3CHO ER -