In case you have non-HTML pages on your website, for example PDFs or spreadsheets, you received’t be able to implement hreflang inside the on the HTML since it doesn’t exist.  Use Google’s URL inspection Device if required to check particular person pages and expose their connection with other language variations https://bookmarkhard.com/story18751571/details-fiction-and-%D0%90%D0%B2%D1%82%D0%BE%D0%BC%D0%B0%D1%82%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B8%D0%B5-%D1%82%D0%B5%D0%B3%D0%B8-hreflang-%D0%B8-%D0%BA%D0%B0%D0%BD%D0%BE%D0%BD%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B8%D0%B5-%D1%82%D0%B5%D0%B3%D0%B8-seo