Finding out where a bogus route is coming from?

Any hints on how to do this?

We have a situation where some person has broadcast a route which is
mapping one of our subnets to the wrong place.
I'm trying to track this at the Mae's to find out what's going on, but I'm
really interested in figuring out how
one can prevent this sort of thing or find out the original source of the
bad route.

Resolving the issue should be straight forward:

  - traceroute to something on that subnet from a few places
    (see amongst others)

  - get a phone number for the noc or whatever of the org that
    announcing your routes, (try whois, or possibly their web
    page... (whatever, get creative))

  - give them a call and explain the situation, open a ticket
    if they have a ticketing system, and move forward from there

You may have to convince them that the problem exists, by forwarding
on traceroute info or whatever. Hopefully their noc staff will be
helpful, reasonable, and clueful.

I have no suggestions for how to prevent this problem from occurring.

Hope this helps,