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Weatherley, A. H. (1963-03-01). "A Note on the Head Kidney and Kidney of the Perch Perca Fluviatilis (linnaeus), with Special Reference to the Blood Vascular System". Proceedings of the Zoological Society of London. 140 (2): 161–167. doi:10.1111/j.1469-7998.1963.tb01859.x. ISSN1469-7998.
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