Szukana fraza: [Abstract = "This paper deals with an H\?\-problem with control constraints for the population dynamics. The biological significance of such a problem is discussed. The necessary and sufficient conditions for the existence of a solution to the suboptimal H\?\-problem for input\-output linear population dynamics with control constraints are established. The last part of this paper contains some considerations about possible applications of H\?\-methods to cancer cell population modelling and control."]