https://ru.wikipedia.org/wiki/%D0%A1%D0%BA%D0%BB%D0%BE%D0%BD%D0%B5%D0%BD%D0%B8%D0%B5_(%D0%BB%D0%B8%D0%BD%D0%B3%D0%B2%D0%B8%D1%81%D1%82%D0%B8%D0%BA%D0%B0)https://rosuchebnik.ru/material/tri-tipa-skloneniya-imen-suschestvitelnyh-russkiy-yazyk-4-klass/