@book{1315,
	author = {Spiegel, Murray R. and Schiller, John J.},
	title = {Probability and statistics },
	publisher = {McGraw-Hill,},
	year = {2009.},
	address = {New York :},
	edition = {3rd ed.},
	url = {https://books.google.com.pk/books?id=cZsAEdXOYNEC&pg=PP3&dq=9780071544252&hl=en&sa=X&ved=2ahUKEwiuh-uU-Nb2AhXv7rsIHfNXAyUQ6AF6BAgLEAI#v=onepage&q=9780071544252&f=false}
}