Origin of pingo-like features on the Beaufort Sea shelf and their possible relationship to decomposing methane gas hydrates - Paull, C.; Ussler III, W.; Dallimore, S.R.; Blasco, S.M.; Lorenson, T.D.; Melling, H.; Medioli, B.E.; Nixon, F.M.; McLaughlin, F.A. (Geophysical Research Letters, 2007)