M.S. Pukhta, Zygmund’s Type Inequality to the Polar Derivative of a Polynomial, Volume 5, International Journal of Advanced Research in Mathematics (Volume 5)
https://www.scipress.com/IJARM.5.52
Abstract:
    In this paper we improve a result recently proved by Irshad et al. [On the Inequalities Concerning to the Polar Derivative of a Polynomial with Restricted Zeroes, Thai Journal of Mathematics, 2014 (Article in Press)] and also extend Zygmund's inequality to the polar derivative of a polynomial.
Keywords:
    Polar Derivative, Polynomials, Zygmund's Inequality