A. Emad Saad Al-deen, “Absorbs Heat from Outside Air and Release it inside the Building by Heat Pump”, J. eng. sustain. dev., vol. 15, no. 4, pp. 189–204, Dec. 2011, Accessed: Jul. 06, 2025. [Online]. Available: https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/1319