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Hedia, M. G., E. - M. S. Belely, S. T. Ismail, and A. - A. M. El-Maaty,
"Monthly changes in testicular blood flow dynamics and their association with testicular volume, plasma steroid hormones profile and semen characteristics in rams",
Theriogenology, vol. 123, issue 1, pp. 68_73, 2019.