We consider meson-baryon interactions in S-wave with strangeness -1. This is a sector populated by plenty of resonances interacting in several two-body coupled channels. We consider a large set of experimental data, where the recent experiments are remarkably accurate. This requires a sound theoretical description to account for all the data and we employ Unitary Chiral Perturbation Theory up to and including O(p^2). The spectroscopy of our solutions is studied within this approach, discussing the rise from the pole content of two Lambda(1405) resonances and of the Lambda(1670), Lambda(1800), Sigma(1480), Sigma(1620) and Sigma(1750). We finally argue about our preferred fit.
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