RT Journal Article SR Electronic T1 Use of a demographic base map for the presentation of areal data in epidemiology. JF British Journal of Preventive & Social Medicine JO Br J Prev Soc Med FD BMJ Publishing Group Ltd SP 165 OP 171 DO 10.1136/jech.20.4.165 VO 20 IS 4 A1 F Forster YR 1966 UL http://jech.bmj.com/content/20/4/165.abstract AB