The existence of a linear horseshoe of continuous maps of dendrites

Assume that a continuous map $f$ defined on a dendrite $X$ has a horseshoe $(A,B)$, where $A$ and $B$ are nonempty disjoint subcontinua in $X$. In this paper we obtain conditions for the structure of sets $A$ and $B$ under which some iteration of $f$ has a linear horseshoe.