Resumen de Onesied approximation and real interpolation

E. Matvejev, N. Krugljak

• It is proved that the reiteration theorem is not valid for the spaces $A^{\theta,q}_p$ defined by V. Popov by means of onesided approximation. It is also proved that a class of cones, defined by onesided approximation of piecewise linear functions on the interval [0, 1], is stable for the real interpolation method.