Currently, the number of solo uses of the 4¢ sheet stamp paying the air mail rate on a penalty permit return receipt card is: 1.

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Description: The 4¢ paying the air mail rate on a government penalty permit return receipt card dated August 27, 1956, mailed to Guam.

Owner/Source: Lot number 1379 in Schuyler Rumsey Philatelic Auctions Catalog for Sale No. 92 with items from Robert Schlesinger's Prexie Postal History Exhibit. The lot realized $250.

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