Final answer:
A cross reference is used to indicate alternate spellings of similar sounding names.
Step-by-step explanation:
In the context of spelling, a cross reference is used to indicate alternate spellings of similar sounding names. For example, if there are different ways to spell a name that sounds similar, a cross reference is needed to guide the correct spelling. This is especially important when dealing with homophones or words with similar pronunciations but different spellings.