This text is devoted to the following result, stemming out works of Bombieri,
Masser, Zannier, and Maurin: Let $X$ be an complex algebraic (projective,
connected) curve and let us consider $n$ rational functions $f_1,...,f_n$ on
$X$ which are multiplicatively independent. The points $x$ of $X$ where their
values $f_1(x),...,f_n(x)$ satisfy at least two independent multiplicative
dependence relations form a finite set.