EntityQ3526998· pop 7· linked from 21 articlesExcision theoremSign in to savemathematical theoremConnectionsmathematicsEntityInternational Standard Book NumberEntityalgebraic topologyEntitycompact spaceEntityinteriorEntityclosureEntitysingular homologyEntityMayer–Vietoris sequenceEntitysuspensionEntityAllen HatcherEntityretractEntityEilenberg–Steenrod axiomsEntitychain homotopyEntityBarycentric subdivisionEntityCategoriesHomology theoryTheorems in topology