Lego Town Trains - 12v Lego Train Layout from 1980's - YouTube
LEGO vintage Train 720 with 12V Electric Motor, incomplete, RARE 42884007201 | eBay
BrickLink - Part bb0012vb : LEGO Electric, Train Motor 12V with Wheels Type II with 3 Round Contact Holes [Electric, Train] - BrickLink Reference Catalog