Submissions from 2015
Laterality Enhances Numerical Skills in the Guppy, Poecilia reticulata, Marco Dadda, Christian Agrillo, Angelo Bisazza, and Culum Brown
Submissions from 2012
Grey Parrot Number Acquisition: the Inference of Cardinal Value from Ordinal Position on the Numeral List, Irene M. Pepperberg and Susan Carey
Submissions from 2006
Grey Parrot (Psittacus erithacus) Numerical Abilities: Addition and Further Experiments on a Zero-Like Concept, Irene M. Pepperberg
Ordinality and Inferential Abilities of a Grey Parrot (Psittacus erithacus), Irene M. Pepperberg
Submissions from 2005
Number Comprehension by a Grey Parrot (Psittacus erithacus), Including a Zero-Like Concept, Irene M. Pepperberg and Jesse D. Gordon
Submissions from 2000
Primate Numerical Competence: Contributions Toward Understanding Nonhuman Cognition, Sarah T. Boysen and Karen I. Hallberg
Submissions from 1999
Overcoming Response Bias Using Symbolic Representations of Number by Chimpanzees (Pan troglodytes), Sarah T. Boysen, Kimberly L. Mukobi, and Gary G. Berntson
Submissions from 1997
Language-Naive Chimpanzees (Pan troglodytes) Judge Relations Between Relations in a Conceptual Matching-to-Sample Task, Roger K.R. Thompson, David L. Oden, and Sarah T. Boysen
Submissions from 1996
Quantity-Based Interference and Symbolic Representations in Chimpanzees (Pan troglodytes), S. T. Boysen, G. G. Berntson, M. B. Hannan, and J. T. Cacioppo
Submissions from 1995
Responses to Quantity: Perceptual Versus Cognitive Mechanisms in Chimpanzees (Pan Troglodytes), Sarah T. Boysen and Gary G. Berntson
Indicating Acts During Counting by a Chimpanzee (Pan troglodytes), Sarah T. Boysen, Gary G. Berntson, Traci A. Shreyer, and Michelle B. Hannan
Submissions from 1994
Numerical Competence in an African Gray Parrot (Psittacus erithacus), Irene M. Pepperberg
Submissions from 1993
Counting in Chimpanzees: Nonhuman Principles and Emergent Properties of Number, Sarah T. Boysen
Submissions from 1989
Numerical Competence in a Chimpanzee (Pan troglodytes), Sarah T. Boysen and Gary G. Berntson
