The file BlowUp is a Maple implementation of: Section 2 in: J. Fullwood and M. van Hoeij, On stringy invariants of GUT vacua. Theorem 1.8 in: M. Esole, P. Jefferson, M. J. Kang, Euler characteristics of crepant resolutions of Weierstrass models. Lemma 3.5 in: J. Fullwood and M. van Hoeij, Stringy Hirzebruch classes of Weierstrass fibrations.