When we want to talk about something that is related to a particular subject, we often use the phrase "in reference to." However, there are several other phrases that we can use instead of this phrase. For example, we can use "regarding," "concerning," "with regard to," "pertaining to," and "relevant to." All of these phrases indicate a connection or relation to a certain topic or idea. Each of them can be used in writing or speaking to provide context and emphasize a discussion point. Varying the use of these synonyms can add depth and variety to your language.