TY  - BOOK
AU  - Harley,J.B.
TI  - Ordnance survey maps: a descriptive manual 
PY  - 1975///
CY  - Southhampton, UK
PB  - Ordnance Survey
KW  - Great Britain
KW  - Ordnance Survey
KW  - Cartography
KW  - Topographic maps
N1  - Bibliography: p. 185-191
ER  -