Extended envelopes around Galactic Cepheids - V. Multi-wavelength and time-dependent analysis of IR excessA. Gallenne, A. Mérand, P. Kervella, G. Pietrzyński, W. Gieren, V. Hocdé, L. Breuval, N. Nardetto and E. LagadecA&A, 651 (2021) A113DOI: https://doi.org/10.1051/0004-6361/202140350