Is there a standard format for entering unknown given names or surnames? I've seen it done a number of ways:
Unknown UNKNOWN, if both are unknown;
Mary UNKNOWN, usually a spouse whose surname is unknown;
Unknown SMITH, sometimes /Smith/ if the given name is unknown;
Mary (-----) or (-----) Smith, and a variety of combinations using question marks. I'd like to be consistent within what I'm doing, but also with what other folks do, since I often share files.