Title supplied by cataloger based on information from sheet label. Image is a photoreduction of the mosaic created from original aerial photographs. Designating symbol SS. Form of individual image numbering: SS-2A-[number], SS-3A-[number], or SS-4A-[number]. Date of publication inferred from dates on individual phootgraphs within the mosaic. "Approximate scale, 1:20,000" [refers to individual images from which mosaic was made].
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