A. Ben-isreal, T. Greville, Generalized inverse: Theory and applications. New York, Springer Verlag, 2nd ed. 2003.
 A. R. Meenakshi, Range symmetric matrices in Minkowski space. Bulletin of Malaysian Math Sci Society, 23 (2000), 45-52.
 |, Generalized inverse of matrices in Minkowski space. Proc. Nat. Seminar Alg. Appln, 1 (2000), 1-14.
 A. R. Meenakshi and D. Krishnaswamy, Product of range symmetric block matrices in minkowski space. Bulletin of Malaysian Math Sci Society 29 ( 2006), 59-68.
 C. Schmoeger, Generalized projections in Banach algebra. Linear Algebra and its Applications, 430 (2009), 601-608.
 D. S. Djordevie, Product of EP operators on Hilbert space. Proc Amer Math Soc., 129 (2000), 1727-1731.
 D. S. Djordjevic, Y. Wei, Operators with equal projections related to their generalized inverse. Applied Mathematics and Computations, 155 (2004), 655-664.
 E. Boasso, On the moore penrose inverse, EP banach space operators and EP banach algebra elements. J Math. Anal. Appl., 339 (2008), 1003-1014.
 H. Schwerdtfeger, Introduction to linear algebra and the theory of matrices. Groningen, P. Noordho, 1950.
 H. Seppo and N. Kenneth, On projections in a space with an indenite metric. Linear Algebra and its Applications. 208/209 (1994), 401-417.
 H. K. Du and Y. Li, The spectral characterization of generalized projections. Linear Algebra Appl. 400 (2005), 313-318.
 I. J. Katz, Wigmann type theorems for EPr matrices. Duke Math J. 32 (1965), 423-428.
 I. Gohberg, P. Lancaster and L. Rodman, Indenite linear algebra and applications. Basel, Boston, Berlin, Brikhauser verlag, 2005.
 J. Gro and K. Trenkler, Generalized and hypergeneralized projectors. Linear Algebra Appl. 364 (1997), 463-474.
 J. Gro, On the product of orthogonal projectors. Linear Algebra and its Applications, 289 (1999), 141-150.
 J. Rebaza, A rst course in applied mathematics. New Jersey , Wiley 2012.
 J. J. Koliha, A simple proof of the product theorem for EP matrices. Linear Algebra and its Applications, 294 (1999), 213-215.
 J. K. Baksalary, O. M. Baksalary and X. Liu, Further properties of generalized and hypergeneralized projectors. Linear Algebra Appl. 389 (2004), 295-303.
 K. Adem, Z. A. Zhour, The representation and approximation for the weighted minkowski inverse in minkowski space. Mathematical and computer modeling, 47 (2008), 363-371.
 L. Lebtahi, N. Thome, A note on k-generalized projections. Linear Algebra Appl. 420 (2007), 572-575.
 M. Pearl, On normal and EPr matrices. Michigan Math J. 6 (1959), 1-5.
 M. Z. Petrovic, S. Stanimirovic, Representation and computation of f2; 3g and f2; 4g-inverses in indefinite inner product spaces. Applied Mathematics and Computation, 254 (2015), 157-171.
 O. Baksalary, G. Trenkler, Functions of orthogonal projectors involving the moore-penrose inverse. Comput. Math. Appl. 59 (2010), 764-778.
 O. M. Baksalary, G. Trenkler, Revisitation of the product of two orthogonal projectors. Linear Algebra and its Applications, 430 (2009), 2813-2833.
 P. R. Halmos, Finite-dimensional vector spaces. New York, Springer Verlag, 1974.
 R. Piziak, P. L. Odell and R. Hahn, Constructing projections on sums and intersections. Comput. Math. Appl. 37 (1999), 67-74.
 R. B. Bapat, J. S. Kirkland and K. M. Prasad, Combinatorial matrix theory and generalized inverses of matrices. New Delhi, Springer Verlag, 2013.
 R. E. Hartwig, I. J. Katz, On product of EP matrices. Linear Algebra and its Applications, 252 (1997), 339-345.
 R. Piziak et. al, Constructing projections on sums and intersections. Compt. Math. Appl. 37 ( 1999), 67-74.
 S. Cheng, Y. Tian, Two sets of new characterizations for normal and EP matrices. Linear Algebra and its Applications, 18 (1975), 327-333.
 S. L. Campbell, C. D. Meyer, EP operators and generalized inverse. Canad Math Bull., 18 (1975), 327-33.
 S. L. Campbell, C.D. Meyer, Generalized inverse of linear transformation. New York, Dover Publications, 1991.
 T. S. Baskett, I. J. Katz, Theorems on product of EPr matrices. Linear Algebra and its Applications, 2 (1969), 87-103.
 Y. Haruo, et al. Projection matrices, generalized inverse matrices and singular value decomposition. New York, Springer Verlag, 2011.
 Y. Tian, G. P. H. Styan, Rank equalities for idempotent and involutory matrices. Linear Algebra Appl. 335 (2001), 101-117.