I am trying to insert the symbol in the title of the question, which I copied from a PDF article, but it appears as space in the output file. What is the corresponding LaTeX command?
The question has already been answered, but for completeness' sake:
The latex commands are:
With the latter two, you will likely want to append
If you want to use the ligatures
This will emulate substitution of unicode characters for certain "latex standard" ligatures which are present as ordinary unicode characters in modern fonts.