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After the previous systematic analysis of $\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}O\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}1,\mathrm{<mrow\; data-mjx-texclass="ORD">18</mrow>}O\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>},\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}O18O16O\mathrm{<mrow\; data-mjx-texclass="ORD">3,4</mrow>}$ in medium infrared, we present here the results of the analysis of new $\mathrm{<mrow\; data-mjx-texclass="ORD">18</mrow>}O16O18O$ observed bands. The spectra have been recorded with the FTS of $Reims5,6$, with a resolution of $0.006cm-1$, and products pathlength $\times$ pressure up to $32m\times 3$ Torr. The data reduction to derive line positions uses a new multifit $program7$. The analysis of spectra is performed using the same formalism as in references [1-4], using standard Watson's Hamiltonian for diagonal blocks and Coriolis and Fermi resonances for off diagonal blocks. 8 polyads have been analysed, among them 7 being analysed for the first time. They correspond to 10 observed bands (underlined) in interaction with ``dark'' bands. $(\nu 1,\nu 3);(\nu 2+\nu 3,\nu 1+\nu 2);(\nu 2+2\nu 3,\nu 1+\nu 2+\nu 3,2\nu 1+\nu 2);(3\nu 3,\nu 1+2\nu 3,2\nu 1+\nu 3);(\nu 2+3\nu 3);(\nu 1+3\nu 3,4\nu 3);(\nu 1+\nu 2+3\nu 3,\nu 2+4\nu 3)and(5\nu 3)$ We give here the range of J and $Ka$ for observed transitions, statistics for energy levels, spectroscopic parameters and resonance coupling parameters. Acknowledgments: Authors thank S.A Tashkun for use of GIP programs, X. Thomas and P. Von der Heyden for recording spectra, L. R'{e}galia and J. J. Plateaux for the use of multifit program. 1. S. M. Mikhailenko, A. Barbe, VI. G. Tyuterev and A. Chichery, Atmos. Oceanic Opt., 12, 9 (1999) 2. A. Chichery, A. Barbe, VI. G. Tyuterev, J. Molecular Spectrosc., 206, 1 - 26 (2001) 3. A. Chichery, A. Brabe, VI. G. Tyuterev, S.A. Tashkun, J. Molecular Spectrosc., 205, 347-349 (2001) 4. M. R. De Backer Barilly, A. Barbe, VI. G. Tyuterev, A. Chichery, Mol. Phys., accepted (2002). 5. J.J. Plateaux, A. Barbe, and A. Delahaigue, Spectrochim. Acta, A 51, 1153-1196 (1995). 6. L. R'{e}galia, Thesis Universit'{e} de Reims, (France) (1996). 7. J.J. Plateaux, L. R'{e}galia, C. Boussin and A. Barbe, J.Q.S.R.T., 68, 507-520 (2001).