It is proved that the reiteration theorem is not valid for the spaces Ap (theta,q) 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.
@article{urn:eudml:doc:40860, title = {Onesided approximation and real interpolation.}, journal = {Collectanea Mathematica}, volume = {48}, year = {1997}, pages = {619-634}, mrnumber = {MR1602612}, zbl = {0892.41007}, language = {en}, url = {http://dml.mathdoc.fr/item/urn:eudml:doc:40860} }
Krugljak, N.; Matvejev, E. Onesided approximation and real interpolation.. Collectanea Mathematica, Tome 48 (1997) pp. 619-634. http://gdmltest.u-ga.fr/item/urn:eudml:doc:40860/