The New Zealand Railways Magazine, Volume 5, Issue 1 (May 1, 1930)
In the new trains are incorporated the very latest practice in railway carriage construction. page 11 Many of the old features of New Zealand carriages have completely disappeared. The windows are of plate glass and are of the balance type, opening from the top to the bottom, like those in a motor car, and they are frameless. Vestibules have been fitted to all cars, thus securing, by an enclosed space, a more complete connection between the carriages, and eliminating the familiar open platform at the ends of the cars.