A two-point problem for first-order systems
The subject of the paper is the periodic boundary value problem \( u' = f(t,u) + \lambda\), \(t\in [a,b]\), \(u(a)=u(b)=0\), where \(f\) is a continuous function from \([a,b]\times \mathbb{R}^n\) into \(\mathbb{R}^n\). Conditions on the function \(f\) are given that there exists \(\lambda \in \mathbb{R}^n\) such that this problem has a classical solution.
scientific article; zbMATH DE number 1798875