Journal of the Transport Ticket Society (492). Kemsing: The Transport Ticket Society: 27–28. January 2005. ISSN0144-347X.{{cite journal}}: CS1 maint: untitled periodical (link)
Journal of the Transport Ticket Society (492). Kemsing: The Transport Ticket Society: 28. January 2005. ISSN0144-347X.{{cite journal}}: CS1 maint: untitled periodical (link)