GSH builder is a free Galois Sub-Hierarchy visualization tool.
The algorithm for calculating GSH is called Pluton and the present
Java realization is based on two articles.
"Efficiently computing a linear extension of the sub-hierarchy of a
Concept Lattice" by Anne Berry, Marianne Huchard,
Ross M. McConnell, Alain Sigayret and Jeremy P. Spinrad.
"Performances of Galois Sub-hierarchy-building algorithms" by
Gabriela Arevalo, Anne Berry, Marianne Huchard,
Guillaume Perrot...