Keyhoe, D. E. (1954). Flying saucers from outer space: By Donald E. Keyhoe (1st print.). Permabooks.
Chicago-viite (17. p.)Keyhoe, Donald E. Flying Saucers from Outer Space: By Donald E. Keyhoe. 1st print. Garden City, NY: Permabooks, 1954.
MLA-viite (8. p.)Keyhoe, Donald E. Flying Saucers from Outer Space: By Donald E. Keyhoe. 1st print. Permabooks, 1954.
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