The phrase "have done previously" is correct and usable in written English.
You can use it to refer to something that has already been done. For example: "I have completed the required steps for this project, as I have done previously."
In the petition, Mr. Birkenfeld's lawyers dispute that claim, as they have done previously.
"We weren't dominating at the worlds like we have done previously.
"Transportation assistance is something that I don't think we have done previously," Will Booher, a FEMA spokesman, said.
The present world, the Maya believed, is doomed to end in cataclysms as the other worlds have done previously.
The implication of that is that there is an explicit policy to do it which is a major change from anything we have done previously.
"It sounds pompous," he said to me once, "but I feel that everything I have done previously was building up to do this".
Indeed, many of these companies continue to use their considerable influence to delay political action, as tobacco companies have done previously.
Like political theorist Hannah Arendt, I believe that before we can act politically we each have to pass judgment on the facts, as I have done previously (pdf).
But instead of shutting down and shutting up as she would have done previously, she said: "I think there's a misunderstanding about what we're talking about.
People always think you use it for the six months, but then four years later they realize "I should have this, where is it?" I think you build a collection on a collection that you have done previously.
"I think what he has done in America is amazing, and what [DJ/producer] Tiesto and Deadmau5 have done, it's what I thought Daft Punk might have done previously.
