caa a22 4500 386360332 CHVBK 20180307111913.0 cr unu---uuuuu 161130e198912 xx s 000 0 eng 10.1017/S0004972700017470 doi S0004972700017470 pii (NATIONALLICENCE)cambridge-10.1017/S0004972700017470 Stavroulakis I. P. Department of Mathematics University of Ioannina 451 10 Ioanniana, Greece A note on a paper of Bowcock and Yu [Elektronische Daten] [I. P. Stavroulakis] Consider the first order differential equation (1) , where pi, and τi, for i = 1, ,n, are positive constants. To find necessary and sufficient conditions, in terms of the coefficients and the delays only, under which all solutions of (1) oscillate, is a problem of great importence. In a recent paper, Bowcock and Yu claimed that is a necessary and sufficient condition for all solutions of (1) to be oscillatory. In this paper a counterexample shows that the above result is not valid and the error in this paper is indicated. Copyright © Australian Mathematical Society 1989 Bulletin of the Australian Mathematical Society Cambridge University Press 40/3(1989-12), 421-424 0004-9727 40:3<421 1989 40 BAZ https://doi.org/10.1017/S0004972700017470 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1017/S0004972700017470 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Stavroulakis I. P. Department of Mathematics University of Ioannina 451 10 Ioanniana, Greece NATIONALLICENCE 773 0- Bulletin of the Australian Mathematical Society Cambridge University Press 40/3(1989-12), 421-424 0004-9727 40:3<421 1989 40 BAZ CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-cambridge