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Linking social complexity and vocal complexity: a parid perspective - Cited by 1 - Krams, Krama, Freeberg, Kullberg, Lucas, Krams, Krama, Freeberg, Kullberg, Lucas - Philosophical Transactions of the Royal Society B: Biological Sciences, 367(1597):1879--1891

2012	Linking social complexity and vocal complexity: a parid perspective - Cited by 1 - Krams, Krama, Freeberg, Kullberg, Lucas, Krams, Krama, Freeberg, Kullberg, Lucas - Philosophical Transactions of the Royal Society B: Biological Sciences, 367(1597):1879--1891
2004	Human uniqueness, learned symbols and recursive thought - Cited by 7 - Hurford - European Review, 12(4):551-565