They are correct all of them.
The original form is σε εμένα (σε = to / εμένα = me)
In modern Greek σε εμένα becomes σ' εμένα for phonetic reasons. (the "ε" from the preposition σε drops off). σ' εμένα is used both in oral and written speech.
σε μένα sounds almost the same as σ' εμένα, it is used in oral speech, but the official form in written speech is σ' εμένα.