Harmonic functions, defined as twice continuously differentiable functions satisfying Laplace’s equation, have long been a subject of intense study in both pure and applied mathematics. Their ...

A new definition of a guiding function for functional differential equations is given, which is sometimes better for applications than the known one by Mawhin. We then prove an existence result for ...

In this paper we consider the numerical solution of initial-value delay-differential-algebraic equations (DDAEs) of retarded and neutral types, with a structure corresponding to that of Hessenberg ...