  Masses and topological charges of the eta and eta' mesons are expressed in
terms of the singlet-octet mixing angle theta. Contributions of the
pseudoscalar 0- continuum are evaluated in a model independant way.
Applications to the decay eta --> 3pi and to the radiative decay of vector
mesons involving eta and eta' are considered. Agreement with experiment is in
general good and the results quite stable for -30.5 <= theta <= -18.5
