

17 different button configurations that were considered for the first pushbutton phones - rms
http://www.mentalfloss.com/blogs/archives/20611

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dchest
In Russia, when they were replacing public dial pay phones with pushbutton
ones in '90s, they chose "Speedometer" type (I-C) for some of them. (Today
most of them are replaced with proper ones, though.)

Another variation from Russia (III-A):
<http://www.tema.ru/travel/komsomolsk/IMG_8694.jpg>

I-B is an interesting configuration - for churches :)

