Title supplied by cataloger based on information from sheet label. Image is a photoreduction of the mosaic created from original aerial photographs. Designating symbol SP. Form of individual image numbering: SP-1A-[number], SP-2A-[number], or SP-3A-[number]. Date of publication inferred from dates on individual photographs within the mosaic. "Approximate scale, 1:20,000" [refers to individual images from which mosaic was made]. Library's copy 2 consists of photographic negatives (4 x 5 in.) corresponding to each of the images in its copy 1.
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