Warfel, H. E. (1950). Otter trawl explorations in Philippine waters. U.S. Govt. Print. Off.
Chicago-viite (17. p.)Warfel, Herbert Elmer. Otter Trawl Explorations in Philippine Waters. Washington: U.S. Govt. Print. Off, 1950.
MLA-viite (9. p.)Warfel, Herbert Elmer. Otter Trawl Explorations in Philippine Waters. U.S. Govt. Print. Off, 1950.
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