"борьба на два фронта" . Koolisõnastikud 2005–2010. Estonian Language Institute, Sõnaveeb 2026. https://sonaveeb.ee/search/unif//kool_KV/%22%D0%B1%D0%BE%D1%80%D1%8C%D0%B1%D0%B0%20%D0%BD%D0%B0%20%D0%B4%D0%B2%D0%B0%20%D1%84%D1%80%D0%BE%D0%BD%D1%82%D0%B0%22/1/rus (13.11.2026)