J. Rose, J.N. Carney, B.N. Silva, and S.J. Booth. 2010. “A Striated, Far Travelled Clast of Rhyolitic Tuff from Thames River Deposits at Ardleigh, Essex, England: Evidence for Early Middle Pleistocene Glaciation in the Thames Catchment”. Netherlands Journal of Geosciences 89 (September):137 -46. https://doi.org/10.1017/S0016774600000743.