31. Inserts nos. 339-477 and 478-558 [Amendments] to Postal laws and regulations (1948 edition); Sept. 26, 1951-[Mar. 28] 1952 and Apr. 2-[Sept. 25] 1952. Bookmark Corporate/Agency Authors: Post Office Department Publisher: Post Office Department SuDoc number: P 1.11/2:948/339-558