Porter, Dot2023-05-232023-05-232015-08-242015-04-25https://repository.upenn.edu/handle/20.500.14332/46439http://hdl.library.upenn.edu/1017/d/medren/5833727World War 1914-1918--Naval operations--SubmarineMagnetic fields--Research--United StatesTechnology CodicesBlueprints (reprographic copies)PhotographsReportsTables (documents)Technical drawingsManuscripts American--20th centuryManuscripts DigitalFacsimile of LJS 192, Submarine detection in an alternating magnetic fieldBook