Philippine Islands. Western Part of Mindanao Sea with Bohol Strait and Part of Tañon Strait. From the United States Government Charts to 1937.

Philippine Islands. Samar and Leyte. San Juanico Strait and Approaches. From the United States Government Surveys to 1935. With Additions and Corrections from the Philippine Gov’t. Charts to 1957. inset: 1) Northern Entrance to San Juanico Strait. From the United States Government Surveys of 1925. With Additions and Corrections from the Philippine Gov’t. Charts to 1957.