On the existence of positive solutions for certain difference equations and inequalities. Philos, Ch.G. — 1998 Journal of Inequalities and Applications [electronic only]
Positive solutions of integrodifferential equations. Philos, Ch.G. — 1993 Journal of Applied Mathematics and Stochastic Analysis
On linear Volterra difference equations with infinite delay. Philos, Ch.G.; Purnaras, I.K. — 2006 Advances in Difference Equations [electronic only]
An asymptotic result for some delay difference equations with continuous variable. Philos, Ch.G.; Purnaras, I.K. — 2004 Advances in Difference Equations [electronic only]
Oscillations in linear difference equations with variable coefficients. Philos, Ch.G.; Purnaras, I.K. — 1991 Journal of Applied Mathematics and Stochastic Analysis
Oscillation and nonoscillation in delay or advanced differential equations and in integrodifferential equations. Kordonis, I.-G.E.; Philos, Ch.G. — 1999 Georgian Mathematical Journal