For a paper discussing selecting various alternates and constructing ligatures see: https://tug.org/TUGboat/Articles/tb24-2/tb77adams.pdf https://tug.org/TUGbo

For a paper discussing selecting various alternates and constructing ligatures see: https://tug.org/TUGboat/Articles/tb24-2/tb77adams.pdf https://tug.org/TUGboat/Articles/tb24-2/tb77adams.pdf