Radiation thermo-chemical models of protoplanetary discs - IV. Modelling CO ro-vibrational emission from Herbig Ae discsW. F. Thi, I. Kamp, P. Woitke, G. van der Plas, R. Bertelsen and L. WiesenfeldA&A, 551 (2013) A49DOI: https://doi.org/10.1051/0004-6361/201219210