If you are correcting only a few small and obvious typos, it may be considered acceptable these days to do so silently. For example, if you follow the *The Chicago Manual of Style* (17th ed.), the following is from section 13.7: > Although in a direct quotation the wording should be reproduced exactly, the following changes are generally permissible to make a passage fit into the syntax and typography of the surrounding text . . . > 6. Obvious typographic errors may be corrected silently (without comment or *sic*), unless the passage quoted is from an older work or a manuscript or other unpublished source where idiosyncrasies of spelling are generally preserved. If spelling and punctuation are modernized or altered for clarity, readers must be so informed in a note, in a preface, or elsewhere. (Several other points were made, but I elided them for the sake of brevity.) --- Of course, if you're writing a thesis, I would check with your instructor or advisor to see what style guide should be followed.