Evidence for azimuthal variations of the oxygen-abundance gradient tracing the spiral structure of the galaxy HCG 91cF. P. A. Vogt, E. Pérez, M. A. Dopita, L. Verdes-Montenegro and S. BorthakurA&A, 601 (2017) A61DOI: https://doi.org/10.1051/0004-6361/201629853
