Numbers 34:3

Then your south side shall be from the wilderness of Zin alongside of Edom, and your southern border shall be from the end of the salt sea eastward;

Genesis 14:3

All these were joined in the vale of Siddim, which is the salt sea.

Ezekiel 47:13

Thus saith the Lord Jehovah: This shall be the border whereby ye shall allot the land as inheritance according to the twelve tribes of Israel: Joseph shall have two portions.

Exodus 23:31

And I will set thy bounds from the Red Sea even unto the sea of the Philistines, and from the wilderness unto the river; for I will give the inhabitants of the land into your hand, that thou mayest dispossess them from before thee.

Joshua 3:16

the waters which flowed down from above stood and rose up in a heap, very far, by Adam, the city that is beside Zaretan; and those that flowed down towards the sea of the plain, the salt sea, were completely cut off. And the people went over opposite to Jericho.

Joshua 15:1-12

And the lot of the tribe of the children of Judah according to their families was: to the border of Edom, the wilderness of Zin, southward, in the extreme south.

Ezekiel 47:8

And he said unto me, These waters issue out toward the east district, and go down into the plain, and go into the sea; when they are brought forth into the sea, the waters thereof shall be healed.

Ezekiel 47:18-23

And on the east side ye shall measure between Hauran and Damascus, and Gilead and the land of Israel by the Jordan, from the border unto the east sea: this is the east side.

Treasury of Scripture Knowledge

Summary

Then your south quarter shall be from the wilderness of Zin along by the coast of Edom, and your south border shall be the outmost coast of the salt sea eastward:

Bible References

South quarter

Exodus 23:31
And I will set thy bounds from the Red Sea even unto the sea of the Philistines, and from the wilderness unto the river; for I will give the inhabitants of the land into your hand, that thou mayest dispossess them from before thee.
Joshua 15:1
And the lot of the tribe of the children of Judah according to their families was: to the border of Edom, the wilderness of Zin, southward, in the extreme south.
Ezekiel 47:13
Thus saith the Lord Jehovah: This shall be the border whereby ye shall allot the land as inheritance according to the twelve tribes of Israel: Joseph shall have two portions.

Salt sea eastward

Joshua 3:16
the waters which flowed down from above stood and rose up in a heap, very far, by Adam, the city that is beside Zaretan; and those that flowed down towards the sea of the plain, the salt sea, were completely cut off. And the people went over opposite to Jericho.
Joshua 15:2
And their southern border was from the end of the salt sea, from the tongue that turns southward;
Ezekiel 47:8
And he said unto me, These waters issue out toward the east district, and go down into the plain, and go into the sea; when they are brought forth into the sea, the waters thereof shall be healed.