What is the ruling on the *iddah* (waiting period) arrangement for a wife who is on a ship when her husband dies, and she has a residence on land?

Primary text

If the wife of the deceased husband, who died on the ship, possesses a residence on land, her ruling is the same as that of a traveler on land, which will be detailed later. If she has no residence other than the ship and there is a suitable chamber on board allowing her to live without mixing with men and where she is safe with her *mahram* (unmarriageable kin), she is obligated to observe the *iddah* there.