I read a post yesterday on acronyms that I wanted to comment on but of course comments were shut down. As a rule, and proper etiquette in writing, if you want to use an acronym and be sure your readers understand, spell out the complete wording of the acronym first, then immediately following put the acronym in parentheses as in Tourist VISA (TR), then you can use the acronym throughout the remainder of the document. I think this will clarify confusion here.