What is your most underappreciated paper?

If you are a scholar working primarily in the social sciences and/or humanities with at least 4000 Google Scholar citations, we hereby invite you to identify one or two publications with publication date 2012 or prior, and for which the count is lower than your present h-index, that you consider underappreciated. It is OK that the publication is coauthored.

…We encourage you to remark briefly on why you select the publication, and to provide a link to it. However, your entire contribution, including the referenced item(s) should be no more than 200 words.

That is from Econ Journal Watch, instructions for participating are at the link.