\references{
Paradis, E. (2007) A Bit-Level Coding Scheme for Nucleotides.
\url{http://ape.mpl.ird.fr/misc/BitLevelCodingScheme_20April2007.pdf}
+
+ Paradis, E. (2012) \emph{Analysis of Phylogenetics and Evolution with
+ R (Second Edition)}. New York: Springer.
}
\author{Emmanuel Paradis}
\seealso{