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Modification in Feeding Regime Reduces the Performance of Surface Breaking Behaviour in a Population of Captive Rays (Raja). Aquarium Sciences and Conservation, 2(3), 171–174
DOI: 10.1023/A:1009615322019

Scott, G.W. & Hull, S.L. & Rollinson, D.J. (1998)
Surface Breaking Behaviour in a Population of Captive Rays Raja: The Expression of a Need to Forage? Aquarium Sciences and Conservation, 2(3), 161–169
DOI: 10.1023/A:1009640022791