by Biggs, D.S., Hoban, P.W., Short, R.P., Smee, R., Schneider, M., Rose, A.
Published in International journal of radiation oncology, biology, physics (01.11.2001)

by Ball, K.A., Biggs, D.S., Hutchings, R.E., Thomson, E.S.
Published in Radiotherapy and oncology (01.10.1995)