Valley formation on early Mars by subglacial and fluvial erosion User snippetscience, in the /r/space: news, articles and discussion subreddit, 11 Aug 2020
Early Mars was covered in ice sheets, not flowing rivers: study | A large number of the valley networks scarring Mars's surface were carved by water melting beneath glacial ice, not by free-flowing rivers as previously thought, according to new UBC research published today in Nature Geoscience User mepper, in the Reddit Science subreddit, 04 Aug 2020
Valley formation on early Mars by subglacial and fluvial erosion User EdwardHeisler, in the The Mars Society: To Explore and Settle a New World! subreddit, 03 Aug 2020