C.A. Nse  , 
    Global Relative Controlability for Nonlinear Neutral Systems with Delays in the Control,
    Research Journal of Applied Sciences,
    Volume 2,Issue 7,
    2007,
    Pages 807-809,
    ISSN 1815-932x,
    rjasci.2007.807.809,
    (https://makhillpublications.co/view-article.php?doi=rjasci.2007.807.809)
    Abstract: Sufficient conditions for global relative controllability of certain types of nonlinear neutral time-varying systems with time-variable delay in the control are given. By a careful linearisation of our system, the results are obtained by use of Schauder’s fixed-point theorem and a generalization of Davison.
    Keywords: Global relative controllability;time-variable delay;Arzela-Ascoli theorem;Schauder`s fixed-point theorem