@book{20399,
	author = {Kumar, S. Arun},
	title = {Principles of Programming Languages:},
	publisher = {Indian Insitiute of Technology},
	address = {Delhi},
	url = {http://video.snu.edu.in/index.php?id=976&cat=Computer Science and  Engineering&course=Principles of Programming Languages&url=Phase1_Video/106102067/lec09.mp4}
}