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Sivak, J.G. (1991)
Elasmobranch Visual Optics. Journal of Experimental Zoology, Supplement, 5, 13–21

Sivak, J.G. & Luer, C.A. (1991)
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Sivak, J.G. (1978)
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Sivak, J.G. (1978)
Optical characteristics of the eye of the spiny dogfish (Squalus acanthias). Revue Canadienne de Biologie, 37(3), 209–217

Sivak, J.G. & Gilbert, P.W. (1976)
Refractive and histological study of accommodation in two species of sharks (Ginglymostoma cirratum and Carcharhinus milberti). Canadian Journal of Zoology, 54(11), 1811–1817
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Accommodations of the lemon shark eye (Negaprion brevirostris). Vision Research, 14(2), 215–216
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