Positive periodic solutions of periodic neutral Lotka–Volterra system with distributed delays

By using a fixed point theorem of strict-set-contraction, some criteria are established for the existence of positive periodic solutions of the following periodic neutral Lotka–Volterra system with distributed delays where (i, j = 1, 2, … , n) are ω-periodic functions, (i, j = 1, 2, … , n) and satisfying , i, j = 1, 2, … , n.