Facta, non verba : eenhedenmachines = unit-machines = machines à unités = Sondermaschinen / Artillerie-Inrichtingen report 195/67/29 Dispersion due to initial perturbations, thrust malalignment and uniform horizontal wind for finned rockets / J.P. Roos report 195/67/73 Dispersion of fin-stabilized rockets due to thrust malalignment in the presence of slow spin / J.P. Roos