Ola, S. I. ., O. C. Daniyan, K. D. . Thomas, and P. A. . Olubunmi. “Effect of Contact With Male on the Physical and Chemical Qualities of Eggs of Black Harco Layers”. Nigerian Journal of Animal Production, vol. 29, no. 1, Jan. 2021, pp. 127-31, doi:10.51791/njap.v29i1.1543.