“…For example, population ecology, control theory, viscous elasticity, and materials with thermal memory, hybrid optical system, in models for physiological processes, red blood cell system, predator-prey models, and so on as the detailed descriptions given in ( [1] , [2] , [3] , [4] , [5] ). A series of papers developed ( [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] ), and many more to obtain an approximate solution for different classes of singularly perturbed differential-difference equations. A variety of different numerical approaches have been suggested in an attempt to obtain accurate and reliable schemes for the treatment of boundary value problems of singularly perturbed differential-difference equations with a small negative shift in the convection term [9, 12].…”