Kurt: Those pesky triple (and more named people). I have some in my family, also.
Personally, if Rutger Markus Olavi is the proper name, I would add Rutger to the proper first name, Markus Olavi to the Middle name just separated by a space and Markus to the preferred name. You should then get Markus Ristniemi with his names in the proper fields for searches, etc.
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