Takafumi Hamano Naofumi Takagi Shuzo Yajima Franco P. Preparata O(n)-depth circuit algorithm for modular exponentiation. 188-192 1995 conf/arith/1995 IEEE Symposium on Computer Arithmetic http://csdl.computer.org/comp/proceedings/arith/1995/7089/00/70890188abs.htm db/conf/arith/arith1995.html#HamanoTYP95