@book{521,
	author = {Hibbeler, R. C.},
	title = {Engineering Mechanics Statics},
	publisher = {Prentice Hall,},
	year = {2010.},
	address = {Upper Saddle River :},
	edition = {12th ed.},
	url = {https://books.google.com.pk/books?id=zjwQzgEACAAJ&dq=Engineering+Mechanics&hl=en&sa=X&redir_esc=y}
}