Citing monkeys?

Does anyone remember reading a paper about the citation history of ape studies? If so, I’d love a pointer or any keyword-details you might remember. I haven’t been able to find it.

For those who are curious: from what I remember, the authors were investigating the what proportion of ape (or was it monkey) studies are truly necessary. They collected citation histories and discovered that a large proportion of studies had received no citations at all. This suggests that although such studies have to clear high hurdles to be approved, our mechanisms are insufficient and as a result we’re putting our cousins through unnecessary hardship.

Interesting to me on a number of levels. 1. It would be a helpful reference for the usage of citation histories. 2. We’ve been to the zoo recently with a gorilla-enthralled two year old.  The apes (and monkeys) act just like some people I know.  Any invasive research (or zookeeping…) had better be worth it.