Watkins, W. Targets and Backgrounds XII: Characterization and Representation. SPIE Digital Library.
Chicago-viite (17. p.)Watkins, Wendell. Targets and Backgrounds XII: Characterization and Representation. SPIE Digital Library.
MLA-viite (9. p.)Watkins, Wendell. Targets and Backgrounds XII: Characterization and Representation. SPIE Digital Library.
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