  We present results of investigations aiming to determine the hadronic
interaction of eta and eta-prime mesons with nucleons. Inferences are based on
comparisons of both the differential cross sections and the close-to-threshold
excitation functions for the p p --> p p eta and p p --> p p eta-prime
reactions with predictions based on the assumption that the kinematically
available phase space is homogeneously populated. We discuss the phenomenology
of the initial and final state interaction, relevance of the hadronic and
quark-gluon degrees of freedom for the reaction dynamics, and explain in detail
the experimental techniques used for the measurement of the meson production in
free and quasi-free collisions of nucleons.
