``volint`` is a command-line script, it should just have double ticks. It is used to check whether VO tables (a specific file format) are valid.

``pedantic`` is an option (so should use double ticks) that allows one to specify whether to check for very strict compliance, or whether to be more relaxed.

``CUNITij`` is the syntax for keywords in FITS files, again an astronomy file format. It should use double ticks.