Richard Beigel William I. Gasarch Ming Li Louxin Zhang Addition in log<sub>2</sub>n + O(1) Steps on Average: A Simple Analysis Electronic Colloquium on Computational Complexity (ECCC) 1996 51 3 db/journals/eccc/eccc3.html#ECCC-TR96-051 http://eccc.hpi-web.de/eccc-reports/1996/TR96-051/index.html