Seconding Penrose. Depending on how broadly you want to cast your net, you could include a sampling of the anti-AI philosophy of mind literature, including Searle, maybe Ned Block, etc. They may not explicitly argue that AIs would keep humans around because we have some mental properties they lack, but you could use those folks' writings as the basis for such an argument.
In fact, I would be personally opposed to activating an allegedly friendly superintelligence if I thought it might forcibly upload everybody, due to uncertainty about whether consciousness would be preserved. I'm not confident that uploads wouldn't be conscious, but neither am I confident that they would be conscious.
Unfortunately, given the orthogonality thesis (why am I not finding the paper on that right now?), this does nothing for my confidence that an AI would not try to forcibly upload or simply exterminate humanity.
As Luke mentioned, I am in the process of writing "Responses to Catastrophic AGI Risk": A journal-bound summary of the AI risk problem, and a taxonomy of the societal proposals (e.g. denial of the risk, no action, legal and economic controls, differential technological development) and AI design proposals (e.g. AI confinement, chaining, Oracle AI, FAI) that have been made.
One of the categories is "They Will Need Us" - claims that AI is no big risk, because AI will always have a need of something that humans have, and that they will therefore preserve us. Currently this section is pretty empty:
But I'm certain that I've heard this claim made more often than in just those two sources. Does anyone remember having seen such arguments somewhere else? While "academically reputable" sources (papers, books) are preferred, blog posts and websites are fine as well.
Note that this claim is distinct from the claim that (due to general economic theory) it's more beneficial for the AIs to trade with us than to destroy us. We already have enough citations for that argument, what we're looking for are arguments saying that destroying humans would mean losing something essentially irreplaceable.