Organized collapse an introduction to discrete Morse theory

Combinatorial topology > Morse theory > Homology theory > Homotopy theory > Manifolds and cell complexes -- PL-topology -- Simple homotopy type, Whitehead torsion, Reidemeister-Franz torsion, etc > Combinatorics -- Graph theory -- Factorization, matching, partitioning, covering > Order, lattices, ordered algebraic structures -- Ordered sets -- Combinatorics of partially ordered sets > Algebraic topology -- Applied homological algebra and category theory -- Simplicial sets and complexes > Manifolds and cell complexes -- Research exposition (monographs, survey articles) > Manifolds and cell complexes -- PL-topology -- General topology of complexes > Global analysis, analysis on manifolds -- Variational problems in infinite-dimensional spaces -- Abstr > Diskrete Morse-Theorie