Please forgive me for replying in English - I can read Norwegian, but not write it.
The parish registers for Wellinghofen are at archion.de (a pay site); however, the record of baptisms only goes through 1888. The civil registry records for Lücklemberg are not online.
There are records for marriages in Wellinghofen through 1905. Do you know anything at all about what Dietrick's father's name or his mother's maiden name might have been, so that we can look for their marriage?