External References
http://www.sdbonline.org/fly/neural/period.htm
http://flybase.org/reports/FBgn0003068.html
Read more about this topic: Period (gene)
Famous quotes containing the word external:
“Given that external reality is a fiction, the writer’s role is almost superfluous. He does not need to invent the fiction because it is already there.”
—J.G. (James Graham)