2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/223917A method of measuring the close to threshold meson production in neutron-neutron collisions is described where the momenta of the colliding neutrons can be determined with the accuracy obtainable for the proton-proton reaction. The technique is based on the double quasi-free nn --> nn X^0 reaction, where deuterons are used as a source of neutrons6 pages, 2 figures, to be published in Phys. Lett. BNuclear Experimenttext