2012 เดกเดฟเดธเด ยท Progress in Nonlinear Differential Equations and Their Applicationsเดชเตเดธเตโเดคเดเด, 24 ยท Springer Science & Business Media
Many boundary value problems are equivalent to Au=O (1) where A : X --+ Y is a mapping between two Banach spaces. When the problem is variational, there exists a differentiable functional rand inf.