Popular Lectures in Mathematics Series, Vol. 1 The Method of Mathematical Induction.by I. S. Sominskii;Popular Lectues in Mathematics Series, Vol. 2 Fibonacci Numbers.by N. N. Vorob'ev;Popular Lectures in Mathematics Series, Vol. 3 Some Applications of Mechanics to Mathematics.by V. A. Uspenskii;Popular Lectures in Mathematics Series, Vol. 4 Geometrical Constructions Using Compasses Only.by A. N. Kostovskii;Popular Lectures in Mathematics Series, Vol. 5 The Ruler in Geometrical Constructions.by A. S. Smogorzhevskii;Popular Lectures in Mathematics Series, Vol. 6 Inequalities.by P. P. Korovkin