Are there guidelines/procedures/conventions for requesting/renewing them? →
In my specific case, my manager at a previous job (~18 mos. ago?) is no longer there. I worked with someone higher up, but I'm not sure if I can/should approach him or what the best way of doing so is. We're connected on LinkedIn, for whatever that's worth, and there's an email address in his profile.
How the heck do people do references? Do they really keep in touch with ex-supervisors from years back?