Extension of Frame's type inequalities to Bessel and modified Bessel   functions
  Our aim is to extend some trigonometric inequalities to Bessel functions. Moreover, we extend the hyperbolic analogue of these trigonometric inequalities. As an application of these results we present a generalization of Cusa-type inequality to modified Bessel function. Our main motivation to write this paper is a recent publication of Chen and S\'andor, which we wish to complement. 
Khaled Mehrez
math.CA