  In this paper, we confirm a conjecture of Orlik-Randell from 1977 on the
Seifert form of chain type invertible singularities. We use Lefschetz
bifibration techniques as developed by Seidel (inspired by Arnold and
Donaldson) and take advantage of the symmetries at hand. We believe that our
method will be useful in understanding the homological/categorical version of
Berglundt-Hubsch mirror conjecture for invertible singularities.
