Image: HoltTractorFrontviewAnd8inchHowitzer

Description: Photograph showing left-front view of a British army Holt artillery tractor, called a caterpillar tractor by the British, on the Western Front, World War I. It appears to be engaged in towing the 8 inch howitzer visible on the right.
Title: HoltTractorFrontviewAnd8inchHowitzer
Credit: "The Times History of the War", Volume X, Page 298, published 1917.
Author: British Government
Permission: This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.
Usage Terms: Public domain
License: Public domain
Attribution Required?: No