His paper "Feather Fracture and the Mechanics of Rock Jointing" introduced the geological community to this newly identified and newly classified fracture patterning, along with its impact in terms of jointing structures.[1][2] He announced it in the summer of 1961. It continues to be the definitive standard of feather fracture work.[3]
^Roberts, John (Summer 1961). "Feather fracture and the mechanics of rock jointing". American Journal of Science. 259: 481–492. doi:10.2475/ajs.259.7.481.
^Roberts, John (1972). "Minor thrust faults in the Avonian of the North Crop of the South Wales Coalfield". Geological Journal. 8 (Part 1): 23–28. doi:10.1002/gj.3350080103.
^"Fracture surface markings in Liassic limestone at Lavernock Point, South Wales". Geological Society, London, Special Publications. 92: 175–186. doi:10.1144/gsl.sp.1995.092.01.09.