If we unite with line segments the midpoints of sides consecutive of each of the congruent parallelograms from a parallelogram divided into parallelograms of order ( m, r ) or ( r, m ) m greater or equal to r, r greater that one, and delete them surplus, is Gets a polygon concave ordered of dato ( m, r, n ) or ( r, m, n ) respectively, m greater than or equal to r, r greater than n, greater or equal to one odd.
