المؤلفون: Darby, H. C., Thompson, F. M. L., Butlin, R., Chapman, J., Yelling, J. A., Armstrong, W. A., Gordon, G., Royle, S. A., Cowlard, K. A., Grant, E. C., Vollans, E. C., Parton, A., Williams, A. M., Daunton, M. J., Laxton, Paul, Barke, M., Dennis, R. J., Lawton, Professor, Kain, R. J. P.

المصدر: The Geographical Journal, 1979 Jul 01. 145(2), 235-241.

URL الوصول: https://www.jstor.org/stable/634389

المؤلفون: Vollans, E. C.

المصدر: Transactions and Papers (Institute of British Geographers), 1959 Jan 01(26), 197-241.

URL الوصول: https://www.jstor.org/stable/621051

المؤلفون: Vollans, E. C.

المصدر: Transactions and Papers (Institute of British Geographers), 1949 Jan 01(15), 93-112.

URL الوصول: https://www.jstor.org/stable/621033