would be my suggestion

Which is the group working there.

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Note added at 12 min (2009-09-02 17:07:48 GMT)
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Or "archeological team" perhaps

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Note added at 12 min (2009-09-02 17:08:27 GMT)
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This one sounds more technical perhaps.

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Note added at 14 min (2009-09-02 17:10:05 GMT)
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"archeologists" to make things simpler, if it may fit in your sentences.

seems to come up quite a bit on the net, in some fairly serious contexts

I'd stick to your first idea, I think it sounds clear enough.

I think the word "archaeological" could be left out if, depending on the wording of the rest of the piece.

Though if it is a heading then I would use it in its entirety.

If, as you say, this is a heading and what follows it a list of organizations/ institutions+names responsible for the project, then I'd go for something like this.

These organizations/institutions have supervised and monitored the project, and contributed in one way or another to its successful outcome.
And authoring articles about the project would fall into the responsibilities of co-ordinating it.

Project Co-ordinators




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Note added at 13 hrs (2009-09-03 06:28:29 GMT)
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My suggestion is obviously targeted to what you offered in the first part of your post. The second paragraph I find a bit confusing, as you seem to hint on a different direction...
'a body that carried out the excavation / archaeological study'

... as does the note you added to Tom's answer
'some of them were accidental finds studied by amateurs.'

Hence, my medium conf. level.