Check out the following links for guidelines and examples of abstract writing
http://lilt.ilstu.edu/ewpeter/geo361/scientific%20abstracts.pdf
http://classweb.gmu.edu/biologyresources/writingguide/Abstract.htm
http://classweb.gmu.edu/biologyresources/writingguide/TitleandAbstract.pdf
http://www.experiment-resources.com/writing-an-abstract.html
