Consulted passages: Definition 2.1.1 and Examples 2.1.2 (printed pp.5–7), Definition 2.1.7 (p.8), Definition 2.1.12 (p.11), Corollary 2.3.10 (p.33), sections 2.5 and 3.2 (holomorphic and continuous functional calculus), and sections 5.5–5.6 (Borel calculus and polar decomposition).