2018-06-122018-06-121957-10-29http://hdl.handle.net/2152.3/9238A Del Mar Engineering Company memorandum with subject: Your Engineering Memo #134 Thornton Letter dated 10-29-1957Del Mar Engineering LabsmemorandumDr. William ThorntonMurrayMcCollumresearchROFEIRadar Optic Firing Error Indicator