ASCII and Unicode quotation marksThese shapes were even sanctioned by an early US version of the ISO 646 standard (ANSI X3.4, also known as ASCII), which defined 0x27 as “apostrophe (closing single quotation mark; acute accent)”, but they should already have been changed when the fonts were extended to cover ISO 8859-1, which added a separate acute accent at 0xB4. One obviously cannot have both 0x27/0x60 and 0x60/0xB4 as mutually
