[1] G. Belitskii, V. Tkachenko, One-Dimensional Functional Equations, Operator Theory: Advances and Applications 144, Birkh˝auser Verlag, Basel, 2003.
[2] J.S. Cassell, Z. Hou, Initial value problem of mixed-type differential equations, Monatshefte Math., 124(1997), 133-145.
[3] V.A. Darzu, Wheeler-Feynman problem on compact interval, Studia Univ. Babe¸s-Bolyai Math., 47(2002), no. 1, 43-46.
[4] R.D. Driver, A “backwards” two-body problem of classical relativistic electrodynamics, The Physical Review, 178(1969), 2051-2057.
[5] L.J. Grimm, H. Schmidt, Boundary value problem for differential equations with deviating arguments, Aequationes Math., 4(1970), 176-180.
[6] Z. Hou, J.S. Cassell, Asymptotic solutions of mixed-type equations with a diagonal matrix, Analysis, 17(1997), 1-12.
[7] V. Hutson, A note on a boundary value problem for linear differential difference equations of mixed type, J. Math. Anal., 61(1977), 416-425.
[8] V.A. Ilea, Functional Differential Equations of First Order with Advanced and Retarded Arguments, Cluj University Press, 2006 (in Romanian).
[9] C.T. Kelley, Solving Nonlinear Equations with Newton’s Method, SIAM, 2003.
[10] J. Mallet-Paret, The Fredholm alternative for functional differential equations of mixed type, J. Dynam. Diff. Eq., 11(1999), no. 1, 1-47.
[11] D. Otrocol, V.A. Ilea, C. Revnic, An iterative method for a functional-differential equations with mixed type argument, Fixed Point Theory, 11(2010), no. 2, 327-336.
[12] R. Precup, Some existence results for differential equations with both retarded and advanced arguments, Mathematica (Cluj), 44(2002), no. 1, 25-31.
[13] I.A. Rus, Functional-differential equations of mixed type, via weakly Picard operators, Seminar on Fixed Point Theory Cluj-Napoca, 3(2002), 335-346.
[14] I.A. Rus, Picard operators and applications, Sciantiae Math. Jpn., 58(2003), no. 1, 191-219.
[15] I.A. Rus, Abstract models of step method which imply the convergence of successive approximations, Fixed Point Theory, 9(2008), no. 1, 293-307.
[16] I.A. Rus, M.A. Serban, D. Trif, Step method for some integral equations from biomathematics, Bull. Math. Soc. Sci. Math. Roumanie, 54(102)(2011), no. 2, 167-183.
[17] I.A. Rus, C. Iancu, Wheeler-Feynman problem for mixed order functional differential equations, Tiberiu Popoviciu Itinerant Seminar of Functional Equations, Approximation and Convexity, Cluj-Napoca, May 23-29, 2000, 197-200.
[18] L.S. Schulman, Some differential difference equations containing both advance and retardation, J. Math. Phys., 15(1974), 195-198.
[19] J. Wu, X. Zou, Asymptotic and periodic boundary value problems of mixed FDEs and wave solutions of lattice differential equations, J. Diff. Eq., 135(1997), 315-357.