on generalisation of brown’s conjecture

Let  $p$ be the complex polynomial of the form $p(z) = z prod_{j=1}^{n-1}(z-z_{j})$, with $|z_{j}|geq 1$, $1 leq j leq n-1.$ then according to famous brown’s conjecture $p’(z) neq 0$, for $|z| < frac{1}{n}.$ this conjecture was proved by aziz and zarger [1]. in this paper, we present some interesting generalisations of this conjecture and the results of several  authors related to this conjecture.