For those who have non-HTML pages on your web site, including PDFs or spreadsheets, you gained’t be capable to carry out hreflang in the with the HTML as it doesn’t exist.  If none of they are utilised, Google will rely on other alerts like hreflang, inner links, and URL length https://socialstrategie.com/story4402154/helping-the-others-realize-the-advantages-of-balises-hreflang-automatiques-et-balises-canoniques-seo