Estate tax. Regulations 80 (1937 edition), estate tax [under title 3 of revenue act of 1926, and under such title as amended by revenue acts of 1928, 1932, 1934, 1935, and 1936, and additional estate tax under title 2 of revenue act of 1932, and under such title as amended by revenue acts of 1934, 1935, and 1936].

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