@article{PismaZhETF.6.707,
    title = {Elastic $\pi^+$ p Scattering Through $90^\circ$ Angle and Contribution of $\Delta_\delta$ Regge Trajectory in the s-Channel},
    author = {Betman, R. G. and Laperashvili, L. V.},
    journal = {πΙΣΨΝΑ Χ φότζ},
    volume = {6},
    issue = {6},
    pages = {707},
    year = {1967},
    doi = {},
    url = {http://jetpletters.ru/ps/0/article_25465.shtml},
}