'Get back to me later'
Comes from the spanish verb 'revertir' meaning 'to revert (to)', and literally means "revert to me".
This can be used in informal speech among friends but also in business letters/conversation.
(1) In a letter or note:
"If you need any more help, me revirte"
(2) In a telephone conversation:
Person A: "Hi, can you talk?"
Person B: "No, sorry I'm really busy."
Person A: "No problem. Me reverte?"
Person B: "OK, I'll call you later. Bye."