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[2] WERBOWSKI J., WYRWINSKA A.: On functional integгability of solutions of differential equations with deviating aгgument. Colloquia Mathematica Societatis Janos Bolyai 30. Qualitative Theory of Differential Equations, Szeged (Hungary), 1979, 1045-1059. MR 0680633

[3] WYRWINSKA A.: On the functional integrability and asymptotic behaviouгs of a ceгtain diffeгential equation with delay. Math. Slovaca 33, 1983, 45-51. MR 0689277