Variational principles for electromagnetic systems with memory

?Saddle point? or ?mini-max? principles are set up for first order integrodifferential systems arising in the hereditary electromagnetic theory. Variational formulations are obtained directly in terms of electric and magnetic field vectors. In particular, these principles are shown to hold as a consequence of thermodynamic restrictions, when the quasi-static case and the linear evolution problem are considered. Entrata in Redazione il 19 febbraio 1999.