Periodic first order linear neutral delay differential equations. - Christos G. Philos; I. K. Purnaras (Appl. Math. Comput., 2001)

Global solutions of a singular initial value problem to second order nonlinear delay differential equations. - Ravi P. Agarwal; Christos G. Philos; P. Ch. Tsamatos (Math. Comput. Model., 2006)

Asymptotic behavior of the oscillatory solutions to first order non-autonomous linear neutral delay differential equations of unstable type. - Christos G. Philos; I. K. Purnaras; Y. G. Sficas (Math. Comput. Model., 2007)

An asymptotic property of the solutions to second order linear nonautonomous delay differential equations. - Christos G. Philos; I. K. Purnaras (Math. Comput. Model., 2009)