86 GHz SiO maser survey of late-type stars in the inner Galaxy - III. Interstellar extinction and colours of the SiO targetsM. Messineo, H. J. Habing, K. M. Menten, A. Omont, L. O. Sjouwerman and F. BertoldiA&A, 435 2 (2005) 575-585DOI: https://doi.org/10.1051/0004-6361:20040533
