http://www.minxlinx.com/hamdocs/first2.htm
http://128.196.64.66/nineplanets/nineplanets/pxearth.html
http://www.blc.arizona.edu/courses/181gh/rick/human_genetics/methods.html
http://129.96.230.155/microbio/virus/links/mirror3/virus.htm
http://www.lib.uiowa.edu/hardin/md/aids.html
http://www.virology.net/Big_Virology/BVretro.html
http://locus.umdnj.edu/nigms/hybrids/hybrids.html
http://www.teaching-biomed.man.ac.uk/student_projects/1999/clegg/Fusion2.htm