TY - RPRT TI - Fission-track ages from the Precambrian of Shropshire AU - C. W. Naeser AU - P. Toghill AU - R. J. Ross PY - 2009 DO - 10.1017/s0016756800025905 UR - https://pubs.usgs.gov/publication/70011846 ID - 70011846 ER -