APMO 1998 Problem 3

Let $a$ , $b$ , $c$ be positive real numbers. Prove that $$\biggl(1+\frac{a}{b}\biggr) \biggl(1+\frac{b}{c}\biggr) \biggl(1+\frac{c}{a}\biggr) \ge 2 \biggl(1+\frac{a+b+c}{\sqrt[3]{abc}}\biggr).$$