Boyd’s Bible Dictionary:
(bone) A city of Judah and Simeon (Josh. 15:29; 19:3). EZEM, elsewhere.
Concise Bible Dictionary:
City on the south of Judah, afterward allotted to Simeon (Josh. 15:29; Josh. 19:3). Supposed to be the same as EZEM. It is not identified.
Jackson’s Dictionary of Scripture Proper Names:
strenuous: bone: self-same