\bib{1994/bernstein}
\yr 1994
\by Daniel J. Bernstein
\paper A non-iterative $2$-adic statement of the $3N+1$ conjecture
\jour Proceedings of the American Mathematical Society
\issn 0002--9939
\vol 121
\pages 405--408
\url http://cr.yp.to/papers.html
\endref