[1] D. D. Anderson, P. V. Camillo, Commutative rings whose elements are a sum of a unit and idempotent, Comm. Algebra, 30 (2002), 3327-3336.
[2] N. Ashra, E. Nasibi, On r-clean rings, Mathematical Reports 2013; 15 (65): No. 2.
[3] G. Azumaya, Strongly -regular rings, J. Fac. Sci. Hokkaido Univ. 13 (1954), 34-39.
[4] P. Ara, -Regular rings have stable range one, Proc. Amer. Math. Soc., 124 (11) (1996), 3293-3298.
[5] A. Badawi, On semicommutative -regular rings, Commun. Algebra, 22 (1) (1993), 151-157.
[6] A. Badawi, Abelian -regular rings, Commun. Algebra, 25 (4) (1997), 1009-1021.
[7] P. V. Camillo, H. P. Hu, Exchange rings, Unit and idempotents, Comm. Algebra. 22 (1994), 4737-4749.
[8] R. Yue Chi Ming, On Von Neumann regular rings , III, Monatshefte fur Mathematik, 86 (1978), 251-257.
[9] P. Danchev, J. Ster,Generalizing -regular ring, Taiwanese J. Math, 19 (6) (2014), 1577-1592.
[10] M. F. Dischinger, Sur les anneaux fortment -reguliers, C. R. Acad. Sci.Paris, Ser. A 283 (1976), 571-573.
[11] K. R. Goodearl, Von Neumann regular rings, Monographs and studied in Math. 4, Pitman, London (1979).
[12] D. Handelman D, Perspectivity and cancellation in regular rings, J. Algebra, 48 (1977), 1-16.
[13] Ch. Huh, N. K. Kim, Y. Lee, Example of strongly -regular rings, Pure Appl. Algera, 189 (2004), 195-210.
[14] Nicholas A. Immormino, Clean rings clean group rings, A Ph.D Dissertation, the Graduate College of Bowling Green, (2013).
[15] T.Y. Lam, A rst course in noncommutative rings, Second edition. Graduate Texts in Mathematics, 131. Springer-Verlag, New York, (2001).
[16] W. K. Nicholson, Clean rings: A Survey, Advances in Ring Theory. Hackensack, NJ: World Sci. Publ., (2005), 181-198.
[17] W. K. Nicholson, Lifting idempotents and exchange rings, Trans. Amer. Math. Soc. 229 (1977) 269-278.
[18] Sh. Safari Sabet, M. Farmani, Extensions of Regular Rings, International Journal of Industrial Mathematics, 8 (4) (2016), 331-337.
[19] Sh. A. Safari Sabet, M. Karami, G-regular and strongly G-regular Rings, IJONS. 26 (5), (2014) 1953-1958.