How to credit?

I don't know if this belongs in this forum or not so please no flaming if I'm in the wrong place. (I'm new to the whole forum thing). Anyway my question is this. If I'm making my own map using custom models that other people have made, how do I give them credit? Do I include a txt file with the map? Do I credit them in the ingame map description? Sorry I'm a noob at this.

It's common to put a fake quest with credits in it (e.g. one requirement per person), but depending on the map type this may not necessarily be appropriate.

On the loading screen is another common way, but if you're using a lot of stuff you'll run out of space there.

The thing about text-file-with-map is that, if it's a multiplayer map, the map will spread without any attachments because that's just how Battle.Net rolls.

I prefer to do it movie style with credits at the end of the map, but I make singleplayer RPGs that lend them selves to that format.

There's plenty of ways to present text ingame. Loading screen, quests, game messages, ability tooltips, transmissions from units etc etc. Not all of them are suitable for showing credits, but at least one of them should work for you. As Rao pointed out, quests are the most often used option. A common setup is to use mandatory quests for gameplay tips and optional quests for credits.

A method that came to my mind right now would be to have "scrolling" credits at the start of the game by displaying game messages one after another. That way, they are in a visible place that doesn't necessarily pause the game for the players. The players should be able to skip/clear the messages by pressing the escape key, though.