Notes
Sixth Column, a novel by Robert A. Heinlein.

First published in condensed form as a serial in Astounding Science-Fiction (January, February and March 1941 issues).

Also appeared as The Day After Tomorrow (1951).

The image opposite and the blurb below are from the 5th printing 1999 of the Baen Books paperback edition, ISBN 067157826X. Cover illustration by Patrick Turner.

Publisher’s Blurb – Lower Cover
SIX TO SAVE A NATION

ROBERT A. HEINLEIN’S CLASSIC NOVEL OF AMERICA UNDER THE HEEL OF THE INVADER.

One by one, the Free Nations had fallen, until America stood alone in arms against the World. Then, as researchers toiled desperately to complete work on a weapon that might yet turn the tide of battle, she too fell.

Now, though scattered resistance flares throughout our continent, the only real hope resides in a mountain redoubt where six men work in secret on a plan to rock the planet...

Alternative Title
The Day After Tomorrow – New English Library Paperback Edition, 1974 printing, SBN 450010856. Cover illustrator unknown.