@book{29170,
	author = {Muhammad Asif Siddiqui, Sufyan Shaikh, Tabish Iqbal & Reema Tariq Mughal},
	title = {Microcontroller Based Private Automatic Branch Exchange},
	publisher = {UIT,},
	year = {2002},
	address = {Karachi:},
	url = {https://drive.google.com/file/d/1DWjYQNF5andQmReaKzZ3-0FG22su8ZsE/view?usp=sharing}
}