%0 Journal Article %A M. A. Mestvirishvili %A I. T. Todorov %T Analytic properties of the meson-nucleon vertex part and scattering amplitudes of pseudoscalar mesons in perturbation theory %J Doklady Akademii Nauk %D 1963 %P 562-565 %V 148 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1963_148_3_a21/ %G ru %F DAN_1963_148_3_a21