@article{BoSc09,
author = {Bostan, Alin and Schost, {\'E}ric},
title = {A simple and fast algorithm for computing exponentials of
power series},
journal = {Information Processing Letters},
number = {13},
year = {2009},
volume = {109},
pages = {754--756},
doi = {10.1016/j.ipl.2009.03.012},
abstract = {As was initially shown by Brent, exponentials of truncated
power series can be computed using a constant number of polynomial
multiplications. This note gives a relatively simple algorithm with a low
constant factor.},
}