On the analogues and generalizations of Squire's theorem (Q1111413)

Assertions consistent with Squire's theorem [see \textit{C. C. Lin}, The theory of hydrodynamic stability (1955; Zbl 0068.392)] based on the simultaneous or separate consideration of the factors responsible for the nonlinearity of the motion and the non-stationarity of the fluid flow whose stability is investigated, are studied. The results may be of interest from the point of view of the practical applications, and can also be used to solve the problem of the degree of generality of the reasons governing the existence of assertions of the type of Squire's theorem.