Mangalloy is vintage, I have it on my 1983ish Lotus Eclaire. Don't count on finding a lot about Lotus on the web, its one of those secondary brands, never made any of their own bikes, but had some really nice ones made for them.
This is one of the more decent threads on Lotus. Use google, there are dozens, if not hundreds of Lotus threads on this forum.
http://www.bikeforums.net/showthread...otus-Road-Bike
The only Lotus catalog I am aware of on the web is a 1981 version.
http://www.wooljersey.com/gallery/v/joe_bunik/lotus/