Lin, C.-C., and Y.-L. Chen. “Using an Oblique Projection Operator for DOA Estimation Of Uniform Linear Array In The Presence Of Mutual Coupling”. International Journal Of Mathematics And Computer Research, Vol. 3, no. 09, Sept. 2015, pp. 1154-6, https://ijmcr.in/index.php/ijmcr/article/view/138.