This Vol. I #1 (1975) Reprint is still available from the National Geographic Society very reasonably priced.  It differs from it's 1964 reprint counterpart only by having a "75" on the inside back cover.  All such "modern" reprints differ from the original issues and the 1922 reprints (below) in size.  These are 6 7/8" x 10" regardless of the Format (1 thru 5).     All such reprints are characterized by clean "shinny" paper that is somewhat heavier than originals.  The word "Reprint" appears in the lower center of each cover.

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