Bip39 Github. It's simple — if you don't be concerned about copyright inheritance, nobody else will — not your computer software or hardware wallet vendors, not your exchanges, rather than your wealth managers. What constitutes a "very good wallet" is one which has crystal clear, very easy to obtain documentation https://bookmarkspecial.com/story19219001/bip39-word-list-pdf-https-linktr-ee-bip39-a-review-of-bip39-generator