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Feb. 20, 2018
February 2018 Puzzle Periodical - A Plethora of Penguins
February 2018 Puzzle Periodical; Puzzle created by David B., NSA Mathematician
Feb. 21, 2017
February 2017 Puzzle Periodical - What is the Connection?
February 2017 Puzzle Periodical; Puzzle created by Wendell W., NSA Cryptanalyst