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Demery, Zoe P.; Chappell, J.; Martin, G. R. «Vision, touch and object manipulation in Senegal parrots Poicephalus senegalus». Proceedings of the Royal Society B, 278, 1725, 2011, pàg. 3687–3693. DOI: 10.1098/rspb.2011.0374. PMC: 3203496. PMID: 21525059.
