\bib{1938/lehmer}
\yr 1938
\by Derrick H. Lehmer
\paper Euclid's algorithm for large numbers
\jour American Mathematical Monthly
\issn 0002--9890
\vol 45
\pages 227--233
\url http://links.jstor.org/sici?sici=0002-9890(193804)45:4<227:EAFLN>2.0.CO;2-Y
\endref