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Consider this question on Stack Overflow,
Morphia Interface for List of enum does not work (unmarshalling)
The same question is on techqa.info.
Are the sites related or is it just spam?
This site is not related to Stack Overflow or Stack Exchange, and it is not spam.
But it is fine since they are linking to the original question on Stack Overflow and also mentioned the names of post authors on Stack Overflow.
They can use it with attribution: