Train platform warning to watch the gap between the subway train and platform, USA Stock Photo - Alamy
Other subway systems urge passengers to 'Mind the Gap' - The Boston Globe
Platform gap - Wikipedia
Honest New York City subway announcements — Quartz
5 Technologies That Could Save the New York Subway
New York subway death: What to do if you're pushed onto the subway tracks?
553 Gap Subway Photos - Free & Royalty-Free Stock Photos from Dreamstime
The Case for the Subway - The New York Times
553 Subway Gap Photos - Free & Royalty-Free Stock Photos from Dreamstime
Please mind the gap between trains and platforms - YouTube
Third rail - Wikipedia
Abandoned Stations : 14 St platforms
The Case for the Subway - The New York Times
The history of the Ottawa subway - Spacing Ottawa
The Case for the Subway - The New York Times
Engineering:Third rail - HandWiki
The Design Thinking Behind London's New $4B Subway Trains | London underground train, Tube train, London underground
Is it possible to survive if you lie along the rail tracks and a train passes over you? - Quora
What You Should Do If You Fall Onto the Subway Tracks
/cdn.vox-cdn.com/uploads/chorus_asset/file/19986261/1223290559.jpg.jpg "Miss the sounds of NYC's subway? Check out this app - The Verge")
Miss the sounds of NYC's subway? Check out this app - The Verge
Platform gap filler - Wikipedia
SEPTA riders overwhelmingly take the bus and subway. Why does Regional Rail receive more funding? - WHYY
/https://public-media.si-cdn.com/filer/f3/7e/f37ef22b-c4c5-4e85-84b1-39638846a1f0/42-16438517.jpg "12 Secrets of the New York Subway | Travel | Smithsonian Magazine")