On toroidal embeddings of 3-folds
The author considers the toric birational morphisms between toric varieties of dimension \(3\) which contract m irreducible divisors to a point. In particular the author studies the question whether they are factorizable in a product of blowings-up of points or not and gives a complete classification for the case \(m\leq 5\), using combinatorial methods. The most important tool for the proof is the ``Farey graph'' associated to such a morphism.
scientific article; zbMATH DE number 4010660