"The Autumn Accelerator" by Peter Leslie : [A story of 'The Invaders' / TV Series created by Larry Cohen].
Corgi Books, #8085, 1969. [FC: Roy Thinnes]: "Over the hills of Provence, France, a huge silver ship glowed in the sky... from its featureless hull came eight small circular craft—that dropped—and landed their cargo—and rose again into the stratosphere... David Vincent — the only man who knew and believed in the existence of the Invaders — began to watch and study the wooded terrain of southern France. And when the forests began to die, the trees to shed their leaves and blacken, he knew that once more he must fight against the alien invasion of "THE INVADERS"!
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https://bearalley.blogspot.com/2010/10/tv-tie-ins-invaders.html
https://www.fantasticfiction.com/l/peter-leslie/autumn-accelerator.htm
https://www.fantasticfiction.com/l/peter-leslie/night-of-trilobites.htm
https://www.fantasticfiction.com/l/peter-leslie/
http://www.sf-encyclopedia.com/entry/leslie_peter
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[About the Author]: Peter Leslie (1922 - 2007) [aka] Ed Mazzaro was one of the two British authors commissioned by Corgi Books (in the UK) to pen original novels based on The Invaders TV show (the other was Rafe Bernard). Leslie's most outright sf ties are his two titles for the Invaders (1967-1968) sequence dealing with insidious Alien Invasion: The Night of the Trilobites (1968) and The Autumn Accelerator (1969), being the third and fourth volumes in this sequence.
Aventura / Crime / Drama / Ficção científica / Literatura Estrangeira / Romance / Suspense e Mistério / Terror