Springer, 1986. — 160 p.
The present book is being published posthumously with the careful assistance of Kenneth Meyer, one of the students of Professor LaSalle. It is appropriate that the last publi cation of Professor LaSalle should be on a subject which con tains many interesting ideas, is very useful in applications and can be understood at an undergraduate level. In addition to making many significant contributions at the research level to differential equations and control theory, he was an excel lent teacher and had the ability to make sophisticated con cepts appear to be very elementary.