January 1950, condition as shown
Extracts from Rule Book British Railways 1950 Booklet
London & North Eastern Railway - Extracts From Rule Book 1933
SR Extracts From Rule Book Instructions Applicable To Electrified Lines 1938 VGC
Extracts from Rule Book British Railways 1950 Booklet very good
LNER Extracts from Rule Book Pamphlet 1933