Sigma-Algebra Definition Metric Space Definition Separable Definition Characterisation of Reflexivity Analysis Peano Kernel Theorem Numerical Analysis Properties of Closed Sets Topology Fredholm Alternative for Compactly Perturbed Elliptic Problems Analysis Turing Instability Conditions Partial Differential Equations Gram-Schmidt Orthonormalisation Functional Analysis Hopf Bifurcation Normal Form Dynamical Systems Coifman--Fefferman Theorem Analysis Analysis Area Measure Theory Subarea