The masses of the excited heavy tetraquarks with hidden charm are calculated
within the relativistic diquark-antidiquark picture. The dynamics of the light
quark in a heavy-light diquark is treated completely relativistically. The
diquark structure is taken into account by calculating the diquark-gluon form
factor. New experimental data on charmonium-like states above open charm
threshold are discussed. The obtained results indicate that X(3872), Y(4260),
Y(4360), Z(4248), Z(4433) and Y(4660) could be tetraquark states with hidden
charm.Comment: 11 page