Bichordal bipartite graph

Bichordal bipartite graph — бихордальный двудольный граф.

A bipartite graph [math]\displaystyle{ G }[/math] is defined as bichordal, if any cycle [math]\displaystyle{ C_{n} }[/math], [math]\displaystyle{ n \gt 4 }[/math], of [math]\displaystyle{ G }[/math] has at least two chords.