Henning Makholm, J. B. Wells. Type inference, principal typings, and let-polymorphism for first-class mixin modules. In Olivier Danvy, Benjamin C. Pierce, editors, Proceedings of the 10th ACM SIGPLAN International Conference on Functional Programming, ICFP 2005, Tallinn, Estonia, September 26-28, 2005. pages 156-167, ACM, 2005. [doi]
Abstract is missing.