Murdoch Gabbay, Aad Mathijssen. One-and-a-halfth-order logic. In Annalisa Bossi, Michael J. Maher, editors, Proceedings of the 8th International ACM SIGPLAN Conference on Principles and Practice of Declarative Programming, July 10-12, 2006, Venice, Italy. pages 189-200, ACM, 2006. [doi]
Abstract is missing.