It's from one of the short stories in Kevin J. Anderson's anthology, "War of the Worlds: Global Dispatches." Effinger's contribution, "The War at Home," has John Carter appearing to Edgar Rice Burroughs after war's end and explaining that the civilized races of Mars have wiped out the invaders, a mutated species of Kaldane known as the Sarmak, and would Earth mind not bothering with a counter-invasion?

"Sarmak" has since become perhaps the most common way to refer to Wells Martians, particularly among hardcore Wold Newton fans.

--The Evil Midnight Lurker what Lurks at Midnight
"An object at rest--CANNOT BE STOPPED!!!"