https://www.cs.odu.edu/~mln/teaching/cs595-s12/?method=display&redirect=http://igor.gold.ac.uk/~dran001/motley/members/fowler56calderon/activity/143594/
https://www.cs.odu.edu/~mln/teaching/cs595-s12/?method=display&redirect=http://igor.gold.ac.uk/~dran001/motley/members/fowler56calderon/activity/143594/