Raz, E., & Reichman-Fried, M. (2006). Attraction rules: Germ cell migration in zebrafish. Current Opinion in Genetics & Development, 16, 355-359. Retrieved from http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6VS0-4K7WJ2V-1-7&_cdi=6248&_user=38661&_orig=browse&_coverDate=08%2F31%2F2006&_sk=999839995&view=c&wchp=dGLbVlb-zSkWb&md5=bfca2d2855d7987a504b708903c73ddd&ie=/sdarticle.pdf.