17.1 Bifurcation Methods 17.2 Portfolio Choices for Small Risks 17.3 Gauge Functions and Asymptotic Expansions 17.4 Method of Undetermined Gauges 17.5 Asympotic Expansions of Integrals 17.6 Hybrid Perturbation-Projection Methods 17.7 Further Reading and Summary 17.8 Exercises